{
  "catalog_version": 1,
  "catalog_id": "cbdf-standard-layouts",
  "title": "CBDF Standard Layout Catalogue",
  "description": "Machine-readable layout registry for CBDF Phase II. Wire field: Styles section LayoutID uint16 LE. Humans pick by slug/title; encoders emit id and STYLE_CONTAINER blocks in pane index order.",
  "governance": [
    "CloudCoin Consortium",
    "Perfect Money Foundation",
    "RAIDA Group"
  ],
  "byte_order": "little_endian",
  "id_ranges": {
    "0x0000-0x00FF": "Legacy compatibility page (1-byte bitfield in low byte)",
    "0x0100-0x01FF": "Named standard desktop layouts (starter set)",
    "0x0200-0x02FF": "Mobile stacks for legacy 0x00-0xFF",
    "0x0300-0x03FF": "Mobile stacks for named 0x0100+",
    "0x0400-0x7FFF": "Reserved future standard catalogue",
    "0x8000-0xEFFF": "Domain / application profiles",
    "0xF000-0xFFFE": "Experimental / private",
    "0xFFFF": "Invalid"
  },
  "canonical_pane_order_rule": [
    "header",
    "left",
    "main_cells_row_major",
    "right",
    "footer",
    "overlay_last"
  ],
  "mobile_stack_rule": [
    "header",
    "main_cells_row_major",
    "left",
    "right",
    "footer",
    "overlay"
  ],
  "default_mobile_breakpoint_px": 768,
  "nav_conventions": {
    "item_block_type": 2,
    "item_separator": "US 0x1F",
    "link_controls": "LINK_START / LINK_END",
    "host_pane": "pane with nav_host=true; typically header or left",
    "mobile_patterns": {
      "hamburger_header": "Collapse nav into header control; drawer or menu overlays main",
      "drawer_left": "Left nav becomes off-canvas drawer",
      "bottom_tabs": "Primary nav moves to footer tab bar",
      "stack": "Nav items listed as normal content in host pane order",
      "hidden": "Nav not shown until user action (Logic Phase III)"
    }
  },
  "encoder_rules": [
    "Write LayoutID as uint16 LE at start of Styles payload.",
    "Open top-level STYLE_CONTAINER blocks in ascending pane index order.",
    "Main grid cells use row-major indices as listed in panes[].",
    "For responsive QWeb, prefer desktop LayoutID and let client switch to pair.mobile_layout_id at breakpoint; or encode mobile-specific documents with mobile LayoutID.",
    "Nav: ITEM_BLOCK type=2 inside the nav_host pane; items separated by US.",
    "Modal/overlay panes should use composite layer_id 10 (modal) or 11 (alert).",
    "If exact layout is required, set Meta Required Features bit 11 when using catalog IDs >= 0x0100."
  ],
  "layout_count": 612,
  "layouts": [
    {
      "id": 0,
      "hex": "0x0000",
      "slug": "legacy-00",
      "title": "Legacy M1x1 (0x00)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x00: header=False, footer=False, left=False, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m1x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 0,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 512,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 512,
      "hex": "0x0200",
      "slug": "legacy-00-mobile",
      "title": "Mobile stack for legacy 0x00",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x00. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 0,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 0
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 1,
      "hex": "0x0001",
      "slug": "legacy-01",
      "title": "Legacy H+M1x1 (0x01)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x01: header=True, footer=False, left=False, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 1,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 513,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 513,
      "hex": "0x0201",
      "slug": "legacy-01-mobile",
      "title": "Mobile stack for legacy 0x01",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x01. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 1,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 1
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 2,
      "hex": "0x0002",
      "slug": "legacy-02",
      "title": "Legacy M1x1+F (0x02)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x02: header=False, footer=True, left=False, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m1x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 2,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 514,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 514,
      "hex": "0x0202",
      "slug": "legacy-02-mobile",
      "title": "Mobile stack for legacy 0x02",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x02. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 2,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 2
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 3,
      "hex": "0x0003",
      "slug": "legacy-03",
      "title": "Legacy H+M1x1+F (0x03)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x03: header=True, footer=True, left=False, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 3,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 515,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 515,
      "hex": "0x0203",
      "slug": "legacy-03-mobile",
      "title": "Mobile stack for legacy 0x03",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x03. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 3,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 3
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 4,
      "hex": "0x0004",
      "slug": "legacy-04",
      "title": "Legacy L+M1x1 (0x04)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x04: header=False, footer=False, left=True, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 4,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 516,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 516,
      "hex": "0x0204",
      "slug": "legacy-04-mobile",
      "title": "Mobile stack for legacy 0x04",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x04. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 4,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 4
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 5,
      "hex": "0x0005",
      "slug": "legacy-05",
      "title": "Legacy H+L+M1x1 (0x05)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x05: header=True, footer=False, left=True, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 5,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 517,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 517,
      "hex": "0x0205",
      "slug": "legacy-05-mobile",
      "title": "Mobile stack for legacy 0x05",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x05. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 5,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 5
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 6,
      "hex": "0x0006",
      "slug": "legacy-06",
      "title": "Legacy L+M1x1+F (0x06)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x06: header=False, footer=True, left=True, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 6,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 518,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 518,
      "hex": "0x0206",
      "slug": "legacy-06-mobile",
      "title": "Mobile stack for legacy 0x06",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x06. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 6,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 6
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 7,
      "hex": "0x0007",
      "slug": "legacy-07",
      "title": "Legacy H+L+M1x1+F (0x07)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x07: header=True, footer=True, left=True, right=False, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 7,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 519,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 519,
      "hex": "0x0207",
      "slug": "legacy-07-mobile",
      "title": "Mobile stack for legacy 0x07",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x07. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 7,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 7
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 8,
      "hex": "0x0008",
      "slug": "legacy-08",
      "title": "Legacy M1x1+R (0x08)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x08: header=False, footer=False, left=False, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m1x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 8,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 520,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 520,
      "hex": "0x0208",
      "slug": "legacy-08-mobile",
      "title": "Mobile stack for legacy 0x08",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x08. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 8,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "right",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 8
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 9,
      "hex": "0x0009",
      "slug": "legacy-09",
      "title": "Legacy H+M1x1+R (0x09)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x09: header=True, footer=False, left=False, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 9,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 521,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 521,
      "hex": "0x0209",
      "slug": "legacy-09-mobile",
      "title": "Mobile stack for legacy 0x09",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x09. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 9,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 9
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 10,
      "hex": "0x000A",
      "slug": "legacy-0a",
      "title": "Legacy M1x1+R+F (0x0A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x0A: header=False, footer=True, left=False, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m1x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 10,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 522,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 522,
      "hex": "0x020A",
      "slug": "legacy-0a-mobile",
      "title": "Mobile stack for legacy 0x0A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x0A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 10,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "right",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 10
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 11,
      "hex": "0x000B",
      "slug": "legacy-0b",
      "title": "Legacy H+M1x1+R+F (0x0B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x0B: header=True, footer=True, left=False, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 11,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 523,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 523,
      "hex": "0x020B",
      "slug": "legacy-0b-mobile",
      "title": "Mobile stack for legacy 0x0B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x0B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 11,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 11
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 12,
      "hex": "0x000C",
      "slug": "legacy-0c",
      "title": "Legacy L+M1x1+R (0x0C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x0C: header=False, footer=False, left=True, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 12,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 524,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 524,
      "hex": "0x020C",
      "slug": "legacy-0c-mobile",
      "title": "Mobile stack for legacy 0x0C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x0C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 12,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 12
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 13,
      "hex": "0x000D",
      "slug": "legacy-0d",
      "title": "Legacy H+L+M1x1+R (0x0D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x0D: header=True, footer=False, left=True, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 13,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 525,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 525,
      "hex": "0x020D",
      "slug": "legacy-0d-mobile",
      "title": "Mobile stack for legacy 0x0D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x0D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 13,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 13
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 14,
      "hex": "0x000E",
      "slug": "legacy-0e",
      "title": "Legacy L+M1x1+R+F (0x0E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x0E: header=False, footer=True, left=True, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 14,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 526,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 526,
      "hex": "0x020E",
      "slug": "legacy-0e-mobile",
      "title": "Mobile stack for legacy 0x0E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x0E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 14,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 14
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 15,
      "hex": "0x000F",
      "slug": "legacy-0f",
      "title": "Legacy H+L+M1x1+R+F (0x0F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x0F: header=True, footer=True, left=True, right=True, main=1\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 15,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 527,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 527,
      "hex": "0x020F",
      "slug": "legacy-0f-mobile",
      "title": "Mobile stack for legacy 0x0F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x0F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 15,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 15
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 16,
      "hex": "0x0010",
      "slug": "legacy-10",
      "title": "Legacy M2x1 (0x10)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x10: header=False, footer=False, left=False, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m2x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 16,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 528,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 528,
      "hex": "0x0210",
      "slug": "legacy-10-mobile",
      "title": "Mobile stack for legacy 0x10",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x10. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 16,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 16
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 17,
      "hex": "0x0011",
      "slug": "legacy-11",
      "title": "Legacy H+M2x1 (0x11)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x11: header=True, footer=False, left=False, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 17,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 529,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 529,
      "hex": "0x0211",
      "slug": "legacy-11-mobile",
      "title": "Mobile stack for legacy 0x11",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x11. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 17,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 17
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 18,
      "hex": "0x0012",
      "slug": "legacy-12",
      "title": "Legacy M2x1+F (0x12)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x12: header=False, footer=True, left=False, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m2x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 18,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 530,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 530,
      "hex": "0x0212",
      "slug": "legacy-12-mobile",
      "title": "Mobile stack for legacy 0x12",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x12. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 18,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 18
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 19,
      "hex": "0x0013",
      "slug": "legacy-13",
      "title": "Legacy H+M2x1+F (0x13)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x13: header=True, footer=True, left=False, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 19,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 531,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 531,
      "hex": "0x0213",
      "slug": "legacy-13-mobile",
      "title": "Mobile stack for legacy 0x13",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x13. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 19,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 19
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 20,
      "hex": "0x0014",
      "slug": "legacy-14",
      "title": "Legacy L+M2x1 (0x14)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x14: header=False, footer=False, left=True, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 20,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 532,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 532,
      "hex": "0x0214",
      "slug": "legacy-14-mobile",
      "title": "Mobile stack for legacy 0x14",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x14. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 20,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 20
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 21,
      "hex": "0x0015",
      "slug": "legacy-15",
      "title": "Legacy H+L+M2x1 (0x15)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x15: header=True, footer=False, left=True, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 21,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 533,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 533,
      "hex": "0x0215",
      "slug": "legacy-15-mobile",
      "title": "Mobile stack for legacy 0x15",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x15. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 21,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 21
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 22,
      "hex": "0x0016",
      "slug": "legacy-16",
      "title": "Legacy L+M2x1+F (0x16)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x16: header=False, footer=True, left=True, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 22,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 534,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 534,
      "hex": "0x0216",
      "slug": "legacy-16-mobile",
      "title": "Mobile stack for legacy 0x16",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x16. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 22,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 22
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 23,
      "hex": "0x0017",
      "slug": "legacy-17",
      "title": "Legacy H+L+M2x1+F (0x17)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x17: header=True, footer=True, left=True, right=False, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 23,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 535,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 535,
      "hex": "0x0217",
      "slug": "legacy-17-mobile",
      "title": "Mobile stack for legacy 0x17",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x17. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 23,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 23
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 24,
      "hex": "0x0018",
      "slug": "legacy-18",
      "title": "Legacy M2x1+R (0x18)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x18: header=False, footer=False, left=False, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m2x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 24,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 536,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 536,
      "hex": "0x0218",
      "slug": "legacy-18-mobile",
      "title": "Mobile stack for legacy 0x18",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x18. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 24,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 24
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 25,
      "hex": "0x0019",
      "slug": "legacy-19",
      "title": "Legacy H+M2x1+R (0x19)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x19: header=True, footer=False, left=False, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 25,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 537,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 537,
      "hex": "0x0219",
      "slug": "legacy-19-mobile",
      "title": "Mobile stack for legacy 0x19",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x19. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 25,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 25
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 26,
      "hex": "0x001A",
      "slug": "legacy-1a",
      "title": "Legacy M2x1+R+F (0x1A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x1A: header=False, footer=True, left=False, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m2x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 26,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 538,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 538,
      "hex": "0x021A",
      "slug": "legacy-1a-mobile",
      "title": "Mobile stack for legacy 0x1A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x1A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 26,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 26
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 27,
      "hex": "0x001B",
      "slug": "legacy-1b",
      "title": "Legacy H+M2x1+R+F (0x1B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x1B: header=True, footer=True, left=False, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 27,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 539,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 539,
      "hex": "0x021B",
      "slug": "legacy-1b-mobile",
      "title": "Mobile stack for legacy 0x1B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x1B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 27,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 27
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 28,
      "hex": "0x001C",
      "slug": "legacy-1c",
      "title": "Legacy L+M2x1+R (0x1C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x1C: header=False, footer=False, left=True, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 28,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 540,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 540,
      "hex": "0x021C",
      "slug": "legacy-1c-mobile",
      "title": "Mobile stack for legacy 0x1C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x1C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 28,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 28
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 29,
      "hex": "0x001D",
      "slug": "legacy-1d",
      "title": "Legacy H+L+M2x1+R (0x1D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x1D: header=True, footer=False, left=True, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 29,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 541,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 541,
      "hex": "0x021D",
      "slug": "legacy-1d-mobile",
      "title": "Mobile stack for legacy 0x1D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x1D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 29,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 29
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 30,
      "hex": "0x001E",
      "slug": "legacy-1e",
      "title": "Legacy L+M2x1+R+F (0x1E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x1E: header=False, footer=True, left=True, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 30,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 542,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 542,
      "hex": "0x021E",
      "slug": "legacy-1e-mobile",
      "title": "Mobile stack for legacy 0x1E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x1E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 30,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 30
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 31,
      "hex": "0x001F",
      "slug": "legacy-1f",
      "title": "Legacy H+L+M2x1+R+F (0x1F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x1F: header=True, footer=True, left=True, right=True, main=2\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 31,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 543,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 543,
      "hex": "0x021F",
      "slug": "legacy-1f-mobile",
      "title": "Mobile stack for legacy 0x1F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x1F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 31,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 31
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 32,
      "hex": "0x0020",
      "slug": "legacy-20",
      "title": "Legacy M3x1 (0x20)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x20: header=False, footer=False, left=False, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m3x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 32,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 544,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 544,
      "hex": "0x0220",
      "slug": "legacy-20-mobile",
      "title": "Mobile stack for legacy 0x20",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x20. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 32,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 32
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 33,
      "hex": "0x0021",
      "slug": "legacy-21",
      "title": "Legacy H+M3x1 (0x21)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x21: header=True, footer=False, left=False, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 33,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 545,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 545,
      "hex": "0x0221",
      "slug": "legacy-21-mobile",
      "title": "Mobile stack for legacy 0x21",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x21. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 33,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 33
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 34,
      "hex": "0x0022",
      "slug": "legacy-22",
      "title": "Legacy M3x1+F (0x22)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x22: header=False, footer=True, left=False, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m3x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 34,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 546,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 546,
      "hex": "0x0222",
      "slug": "legacy-22-mobile",
      "title": "Mobile stack for legacy 0x22",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x22. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 34,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 34
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 35,
      "hex": "0x0023",
      "slug": "legacy-23",
      "title": "Legacy H+M3x1+F (0x23)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x23: header=True, footer=True, left=False, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 35,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 547,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 547,
      "hex": "0x0223",
      "slug": "legacy-23-mobile",
      "title": "Mobile stack for legacy 0x23",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x23. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 35,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 35
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 36,
      "hex": "0x0024",
      "slug": "legacy-24",
      "title": "Legacy L+M3x1 (0x24)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x24: header=False, footer=False, left=True, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 36,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 548,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 548,
      "hex": "0x0224",
      "slug": "legacy-24-mobile",
      "title": "Mobile stack for legacy 0x24",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x24. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 36,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 36
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 37,
      "hex": "0x0025",
      "slug": "legacy-25",
      "title": "Legacy H+L+M3x1 (0x25)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x25: header=True, footer=False, left=True, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 37,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 549,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 549,
      "hex": "0x0225",
      "slug": "legacy-25-mobile",
      "title": "Mobile stack for legacy 0x25",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x25. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 37,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 37
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 38,
      "hex": "0x0026",
      "slug": "legacy-26",
      "title": "Legacy L+M3x1+F (0x26)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x26: header=False, footer=True, left=True, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 38,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 550,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 550,
      "hex": "0x0226",
      "slug": "legacy-26-mobile",
      "title": "Mobile stack for legacy 0x26",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x26. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 38,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 38
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 39,
      "hex": "0x0027",
      "slug": "legacy-27",
      "title": "Legacy H+L+M3x1+F (0x27)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x27: header=True, footer=True, left=True, right=False, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 39,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 551,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 551,
      "hex": "0x0227",
      "slug": "legacy-27-mobile",
      "title": "Mobile stack for legacy 0x27",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x27. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 39,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 39
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 40,
      "hex": "0x0028",
      "slug": "legacy-28",
      "title": "Legacy M3x1+R (0x28)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x28: header=False, footer=False, left=False, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m3x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 40,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 552,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 552,
      "hex": "0x0228",
      "slug": "legacy-28-mobile",
      "title": "Mobile stack for legacy 0x28",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x28. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 40,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 40
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 41,
      "hex": "0x0029",
      "slug": "legacy-29",
      "title": "Legacy H+M3x1+R (0x29)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x29: header=True, footer=False, left=False, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 41,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 553,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 553,
      "hex": "0x0229",
      "slug": "legacy-29-mobile",
      "title": "Mobile stack for legacy 0x29",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x29. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 41,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 41
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 42,
      "hex": "0x002A",
      "slug": "legacy-2a",
      "title": "Legacy M3x1+R+F (0x2A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x2A: header=False, footer=True, left=False, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m3x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 42,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 554,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 554,
      "hex": "0x022A",
      "slug": "legacy-2a-mobile",
      "title": "Mobile stack for legacy 0x2A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x2A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 42,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 42
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 43,
      "hex": "0x002B",
      "slug": "legacy-2b",
      "title": "Legacy H+M3x1+R+F (0x2B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x2B: header=True, footer=True, left=False, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 43,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 555,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 555,
      "hex": "0x022B",
      "slug": "legacy-2b-mobile",
      "title": "Mobile stack for legacy 0x2B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x2B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 43,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 43
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 44,
      "hex": "0x002C",
      "slug": "legacy-2c",
      "title": "Legacy L+M3x1+R (0x2C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x2C: header=False, footer=False, left=True, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 44,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 556,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 556,
      "hex": "0x022C",
      "slug": "legacy-2c-mobile",
      "title": "Mobile stack for legacy 0x2C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x2C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 44,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 44
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 45,
      "hex": "0x002D",
      "slug": "legacy-2d",
      "title": "Legacy H+L+M3x1+R (0x2D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x2D: header=True, footer=False, left=True, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 45,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 557,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 557,
      "hex": "0x022D",
      "slug": "legacy-2d-mobile",
      "title": "Mobile stack for legacy 0x2D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x2D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 45,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 45
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 46,
      "hex": "0x002E",
      "slug": "legacy-2e",
      "title": "Legacy L+M3x1+R+F (0x2E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x2E: header=False, footer=True, left=True, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 46,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 558,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 558,
      "hex": "0x022E",
      "slug": "legacy-2e-mobile",
      "title": "Mobile stack for legacy 0x2E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x2E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 46,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 46
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 47,
      "hex": "0x002F",
      "slug": "legacy-2f",
      "title": "Legacy H+L+M3x1+R+F (0x2F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x2F: header=True, footer=True, left=True, right=True, main=3\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 47,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 559,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 559,
      "hex": "0x022F",
      "slug": "legacy-2f-mobile",
      "title": "Mobile stack for legacy 0x2F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x2F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 47,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 47
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 48,
      "hex": "0x0030",
      "slug": "legacy-30",
      "title": "Legacy M4x1 (0x30)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x30: header=False, footer=False, left=False, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m4x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 48,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 560,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 560,
      "hex": "0x0230",
      "slug": "legacy-30-mobile",
      "title": "Mobile stack for legacy 0x30",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x30. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 48,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 48
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 49,
      "hex": "0x0031",
      "slug": "legacy-31",
      "title": "Legacy H+M4x1 (0x31)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x31: header=True, footer=False, left=False, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 49,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 561,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 561,
      "hex": "0x0231",
      "slug": "legacy-31-mobile",
      "title": "Mobile stack for legacy 0x31",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x31. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 49,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 49
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 50,
      "hex": "0x0032",
      "slug": "legacy-32",
      "title": "Legacy M4x1+F (0x32)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x32: header=False, footer=True, left=False, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m4x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 50,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 562,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 562,
      "hex": "0x0232",
      "slug": "legacy-32-mobile",
      "title": "Mobile stack for legacy 0x32",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x32. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 50,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 50
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 51,
      "hex": "0x0033",
      "slug": "legacy-33",
      "title": "Legacy H+M4x1+F (0x33)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x33: header=True, footer=True, left=False, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 51,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 563,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 563,
      "hex": "0x0233",
      "slug": "legacy-33-mobile",
      "title": "Mobile stack for legacy 0x33",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x33. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 51,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 51
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 52,
      "hex": "0x0034",
      "slug": "legacy-34",
      "title": "Legacy L+M4x1 (0x34)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x34: header=False, footer=False, left=True, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 52,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 564,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 564,
      "hex": "0x0234",
      "slug": "legacy-34-mobile",
      "title": "Mobile stack for legacy 0x34",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x34. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 52,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 52
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 53,
      "hex": "0x0035",
      "slug": "legacy-35",
      "title": "Legacy H+L+M4x1 (0x35)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x35: header=True, footer=False, left=True, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x1"
      ],
      "viewport": "desktop",
      "legacy_byte": 53,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 565,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 565,
      "hex": "0x0235",
      "slug": "legacy-35-mobile",
      "title": "Mobile stack for legacy 0x35",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x35. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 53,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 53
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 54,
      "hex": "0x0036",
      "slug": "legacy-36",
      "title": "Legacy L+M4x1+F (0x36)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x36: header=False, footer=True, left=True, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 54,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 566,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 566,
      "hex": "0x0236",
      "slug": "legacy-36-mobile",
      "title": "Mobile stack for legacy 0x36",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x36. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 54,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 54
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 55,
      "hex": "0x0037",
      "slug": "legacy-37",
      "title": "Legacy H+L+M4x1+F (0x37)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x37: header=True, footer=True, left=True, right=False, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x1+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 55,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 567,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 567,
      "hex": "0x0237",
      "slug": "legacy-37-mobile",
      "title": "Mobile stack for legacy 0x37",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x37. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 55,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 55
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 56,
      "hex": "0x0038",
      "slug": "legacy-38",
      "title": "Legacy M4x1+R (0x38)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x38: header=False, footer=False, left=False, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m4x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 56,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 568,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 568,
      "hex": "0x0238",
      "slug": "legacy-38-mobile",
      "title": "Mobile stack for legacy 0x38",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x38. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 56,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 56
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 57,
      "hex": "0x0039",
      "slug": "legacy-39",
      "title": "Legacy H+M4x1+R (0x39)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x39: header=True, footer=False, left=False, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 57,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 569,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 569,
      "hex": "0x0239",
      "slug": "legacy-39-mobile",
      "title": "Mobile stack for legacy 0x39",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x39. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 57,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 57
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 58,
      "hex": "0x003A",
      "slug": "legacy-3a",
      "title": "Legacy M4x1+R+F (0x3A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x3A: header=False, footer=True, left=False, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "m4x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 58,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 570,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 570,
      "hex": "0x023A",
      "slug": "legacy-3a-mobile",
      "title": "Mobile stack for legacy 0x3A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x3A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 58,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 58
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 59,
      "hex": "0x003B",
      "slug": "legacy-3b",
      "title": "Legacy H+M4x1+R+F (0x3B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x3B: header=True, footer=True, left=False, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 59,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 571,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 571,
      "hex": "0x023B",
      "slug": "legacy-3b-mobile",
      "title": "Mobile stack for legacy 0x3B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x3B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 59,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 59
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 60,
      "hex": "0x003C",
      "slug": "legacy-3c",
      "title": "Legacy L+M4x1+R (0x3C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x3C: header=False, footer=False, left=True, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 60,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 572,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 572,
      "hex": "0x023C",
      "slug": "legacy-3c-mobile",
      "title": "Mobile stack for legacy 0x3C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x3C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 60,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 60
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 61,
      "hex": "0x003D",
      "slug": "legacy-3d",
      "title": "Legacy H+L+M4x1+R (0x3D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x3D: header=True, footer=False, left=True, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x1+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 61,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 573,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 573,
      "hex": "0x023D",
      "slug": "legacy-3d-mobile",
      "title": "Mobile stack for legacy 0x3D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x3D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 61,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 61
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 62,
      "hex": "0x003E",
      "slug": "legacy-3e",
      "title": "Legacy L+M4x1+R+F (0x3E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x3E: header=False, footer=True, left=True, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 62,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 574,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 574,
      "hex": "0x023E",
      "slug": "legacy-3e-mobile",
      "title": "Mobile stack for legacy 0x3E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x3E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 62,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 62
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 63,
      "hex": "0x003F",
      "slug": "legacy-3f",
      "title": "Legacy H+L+M4x1+R+F (0x3F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x3F: header=True, footer=True, left=True, right=True, main=4\u00d71.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x1+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 63,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 575,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 575,
      "hex": "0x023F",
      "slug": "legacy-3f-mobile",
      "title": "Mobile stack for legacy 0x3F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x3F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 63,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 63
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 64,
      "hex": "0x0040",
      "slug": "legacy-40",
      "title": "Legacy M1x2 (0x40)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x40: header=False, footer=False, left=False, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m1x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 64,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 576,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 576,
      "hex": "0x0240",
      "slug": "legacy-40-mobile",
      "title": "Mobile stack for legacy 0x40",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x40. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 64,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 64
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 65,
      "hex": "0x0041",
      "slug": "legacy-41",
      "title": "Legacy H+M1x2 (0x41)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x41: header=True, footer=False, left=False, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 65,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 577,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 577,
      "hex": "0x0241",
      "slug": "legacy-41-mobile",
      "title": "Mobile stack for legacy 0x41",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x41. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 65,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 65
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 66,
      "hex": "0x0042",
      "slug": "legacy-42",
      "title": "Legacy M1x2+F (0x42)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x42: header=False, footer=True, left=False, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m1x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 66,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 578,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 578,
      "hex": "0x0242",
      "slug": "legacy-42-mobile",
      "title": "Mobile stack for legacy 0x42",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x42. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 66,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 66
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 67,
      "hex": "0x0043",
      "slug": "legacy-43",
      "title": "Legacy H+M1x2+F (0x43)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x43: header=True, footer=True, left=False, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 67,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 579,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 579,
      "hex": "0x0243",
      "slug": "legacy-43-mobile",
      "title": "Mobile stack for legacy 0x43",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x43. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 67,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 67
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 68,
      "hex": "0x0044",
      "slug": "legacy-44",
      "title": "Legacy L+M1x2 (0x44)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x44: header=False, footer=False, left=True, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 68,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 580,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 580,
      "hex": "0x0244",
      "slug": "legacy-44-mobile",
      "title": "Mobile stack for legacy 0x44",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x44. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 68,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 68
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 69,
      "hex": "0x0045",
      "slug": "legacy-45",
      "title": "Legacy H+L+M1x2 (0x45)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x45: header=True, footer=False, left=True, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 69,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 581,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 581,
      "hex": "0x0245",
      "slug": "legacy-45-mobile",
      "title": "Mobile stack for legacy 0x45",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x45. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 69,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 69
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 70,
      "hex": "0x0046",
      "slug": "legacy-46",
      "title": "Legacy L+M1x2+F (0x46)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x46: header=False, footer=True, left=True, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 70,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 582,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 582,
      "hex": "0x0246",
      "slug": "legacy-46-mobile",
      "title": "Mobile stack for legacy 0x46",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x46. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 70,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 70
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 71,
      "hex": "0x0047",
      "slug": "legacy-47",
      "title": "Legacy H+L+M1x2+F (0x47)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x47: header=True, footer=True, left=True, right=False, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 71,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 583,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 583,
      "hex": "0x0247",
      "slug": "legacy-47-mobile",
      "title": "Mobile stack for legacy 0x47",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x47. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 71,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 71
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 72,
      "hex": "0x0048",
      "slug": "legacy-48",
      "title": "Legacy M1x2+R (0x48)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x48: header=False, footer=False, left=False, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m1x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 72,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 584,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 584,
      "hex": "0x0248",
      "slug": "legacy-48-mobile",
      "title": "Mobile stack for legacy 0x48",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x48. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 72,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 72
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 73,
      "hex": "0x0049",
      "slug": "legacy-49",
      "title": "Legacy H+M1x2+R (0x49)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x49: header=True, footer=False, left=False, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 73,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 585,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 585,
      "hex": "0x0249",
      "slug": "legacy-49-mobile",
      "title": "Mobile stack for legacy 0x49",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x49. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 73,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 73
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 74,
      "hex": "0x004A",
      "slug": "legacy-4a",
      "title": "Legacy M1x2+R+F (0x4A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x4A: header=False, footer=True, left=False, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m1x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 74,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 586,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 586,
      "hex": "0x024A",
      "slug": "legacy-4a-mobile",
      "title": "Mobile stack for legacy 0x4A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x4A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 74,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 74
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 75,
      "hex": "0x004B",
      "slug": "legacy-4b",
      "title": "Legacy H+M1x2+R+F (0x4B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x4B: header=True, footer=True, left=False, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 75,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 587,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 587,
      "hex": "0x024B",
      "slug": "legacy-4b-mobile",
      "title": "Mobile stack for legacy 0x4B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x4B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 75,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 75
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 76,
      "hex": "0x004C",
      "slug": "legacy-4c",
      "title": "Legacy L+M1x2+R (0x4C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x4C: header=False, footer=False, left=True, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 76,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 588,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 588,
      "hex": "0x024C",
      "slug": "legacy-4c-mobile",
      "title": "Mobile stack for legacy 0x4C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x4C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 76,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 76
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 77,
      "hex": "0x004D",
      "slug": "legacy-4d",
      "title": "Legacy H+L+M1x2+R (0x4D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x4D: header=True, footer=False, left=True, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 77,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 589,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 589,
      "hex": "0x024D",
      "slug": "legacy-4d-mobile",
      "title": "Mobile stack for legacy 0x4D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x4D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 77,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 77
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 78,
      "hex": "0x004E",
      "slug": "legacy-4e",
      "title": "Legacy L+M1x2+R+F (0x4E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x4E: header=False, footer=True, left=True, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 78,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 590,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 590,
      "hex": "0x024E",
      "slug": "legacy-4e-mobile",
      "title": "Mobile stack for legacy 0x4E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x4E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 78,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 78
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 79,
      "hex": "0x004F",
      "slug": "legacy-4f",
      "title": "Legacy H+L+M1x2+R+F (0x4F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x4F: header=True, footer=True, left=True, right=True, main=1\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 79,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 591,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 591,
      "hex": "0x024F",
      "slug": "legacy-4f-mobile",
      "title": "Mobile stack for legacy 0x4F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x4F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 79,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 79
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 80,
      "hex": "0x0050",
      "slug": "legacy-50",
      "title": "Legacy M2x2 (0x50)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x50: header=False, footer=False, left=False, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m2x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 80,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 592,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 592,
      "hex": "0x0250",
      "slug": "legacy-50-mobile",
      "title": "Mobile stack for legacy 0x50",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x50. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 80,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 80
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 81,
      "hex": "0x0051",
      "slug": "legacy-51",
      "title": "Legacy H+M2x2 (0x51)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x51: header=True, footer=False, left=False, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 81,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 593,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 593,
      "hex": "0x0251",
      "slug": "legacy-51-mobile",
      "title": "Mobile stack for legacy 0x51",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x51. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 81,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 81
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 82,
      "hex": "0x0052",
      "slug": "legacy-52",
      "title": "Legacy M2x2+F (0x52)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x52: header=False, footer=True, left=False, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m2x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 82,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 594,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 594,
      "hex": "0x0252",
      "slug": "legacy-52-mobile",
      "title": "Mobile stack for legacy 0x52",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x52. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 82,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 82
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 83,
      "hex": "0x0053",
      "slug": "legacy-53",
      "title": "Legacy H+M2x2+F (0x53)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x53: header=True, footer=True, left=False, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 83,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 595,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 595,
      "hex": "0x0253",
      "slug": "legacy-53-mobile",
      "title": "Mobile stack for legacy 0x53",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x53. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 83,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 83
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 84,
      "hex": "0x0054",
      "slug": "legacy-54",
      "title": "Legacy L+M2x2 (0x54)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x54: header=False, footer=False, left=True, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 84,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 596,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 596,
      "hex": "0x0254",
      "slug": "legacy-54-mobile",
      "title": "Mobile stack for legacy 0x54",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x54. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 84,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 84
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 85,
      "hex": "0x0055",
      "slug": "legacy-55",
      "title": "Legacy H+L+M2x2 (0x55)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x55: header=True, footer=False, left=True, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 85,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 597,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 597,
      "hex": "0x0255",
      "slug": "legacy-55-mobile",
      "title": "Mobile stack for legacy 0x55",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x55. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 85,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 85
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 86,
      "hex": "0x0056",
      "slug": "legacy-56",
      "title": "Legacy L+M2x2+F (0x56)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x56: header=False, footer=True, left=True, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 86,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 598,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 598,
      "hex": "0x0256",
      "slug": "legacy-56-mobile",
      "title": "Mobile stack for legacy 0x56",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x56. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 86,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 86
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 87,
      "hex": "0x0057",
      "slug": "legacy-57",
      "title": "Legacy H+L+M2x2+F (0x57)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x57: header=True, footer=True, left=True, right=False, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 87,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 599,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 599,
      "hex": "0x0257",
      "slug": "legacy-57-mobile",
      "title": "Mobile stack for legacy 0x57",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x57. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 87,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 87
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 88,
      "hex": "0x0058",
      "slug": "legacy-58",
      "title": "Legacy M2x2+R (0x58)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x58: header=False, footer=False, left=False, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m2x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 88,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 600,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 600,
      "hex": "0x0258",
      "slug": "legacy-58-mobile",
      "title": "Mobile stack for legacy 0x58",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x58. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 88,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 88
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 89,
      "hex": "0x0059",
      "slug": "legacy-59",
      "title": "Legacy H+M2x2+R (0x59)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x59: header=True, footer=False, left=False, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 89,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 601,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 601,
      "hex": "0x0259",
      "slug": "legacy-59-mobile",
      "title": "Mobile stack for legacy 0x59",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x59. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 89,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 89
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 90,
      "hex": "0x005A",
      "slug": "legacy-5a",
      "title": "Legacy M2x2+R+F (0x5A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x5A: header=False, footer=True, left=False, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m2x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 90,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 602,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 602,
      "hex": "0x025A",
      "slug": "legacy-5a-mobile",
      "title": "Mobile stack for legacy 0x5A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x5A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 90,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 90
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 91,
      "hex": "0x005B",
      "slug": "legacy-5b",
      "title": "Legacy H+M2x2+R+F (0x5B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x5B: header=True, footer=True, left=False, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 91,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 603,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 603,
      "hex": "0x025B",
      "slug": "legacy-5b-mobile",
      "title": "Mobile stack for legacy 0x5B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x5B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 91,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 91
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 92,
      "hex": "0x005C",
      "slug": "legacy-5c",
      "title": "Legacy L+M2x2+R (0x5C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x5C: header=False, footer=False, left=True, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 92,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 604,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 604,
      "hex": "0x025C",
      "slug": "legacy-5c-mobile",
      "title": "Mobile stack for legacy 0x5C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x5C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 92,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 92
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 93,
      "hex": "0x005D",
      "slug": "legacy-5d",
      "title": "Legacy H+L+M2x2+R (0x5D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x5D: header=True, footer=False, left=True, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 93,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 605,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 605,
      "hex": "0x025D",
      "slug": "legacy-5d-mobile",
      "title": "Mobile stack for legacy 0x5D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x5D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 93,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 93
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 94,
      "hex": "0x005E",
      "slug": "legacy-5e",
      "title": "Legacy L+M2x2+R+F (0x5E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x5E: header=False, footer=True, left=True, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 94,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 606,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 606,
      "hex": "0x025E",
      "slug": "legacy-5e-mobile",
      "title": "Mobile stack for legacy 0x5E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x5E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 94,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 94
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 95,
      "hex": "0x005F",
      "slug": "legacy-5f",
      "title": "Legacy H+L+M2x2+R+F (0x5F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x5F: header=True, footer=True, left=True, right=True, main=2\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 95,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 607,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 607,
      "hex": "0x025F",
      "slug": "legacy-5f-mobile",
      "title": "Mobile stack for legacy 0x5F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x5F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 95,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 95
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 96,
      "hex": "0x0060",
      "slug": "legacy-60",
      "title": "Legacy M3x2 (0x60)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x60: header=False, footer=False, left=False, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m3x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 96,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 608,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 608,
      "hex": "0x0260",
      "slug": "legacy-60-mobile",
      "title": "Mobile stack for legacy 0x60",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x60. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 96,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 96
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 97,
      "hex": "0x0061",
      "slug": "legacy-61",
      "title": "Legacy H+M3x2 (0x61)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x61: header=True, footer=False, left=False, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 97,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 609,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 609,
      "hex": "0x0261",
      "slug": "legacy-61-mobile",
      "title": "Mobile stack for legacy 0x61",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x61. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 97,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 97
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 98,
      "hex": "0x0062",
      "slug": "legacy-62",
      "title": "Legacy M3x2+F (0x62)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x62: header=False, footer=True, left=False, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m3x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 98,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 610,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 610,
      "hex": "0x0262",
      "slug": "legacy-62-mobile",
      "title": "Mobile stack for legacy 0x62",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x62. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 98,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 98
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 99,
      "hex": "0x0063",
      "slug": "legacy-63",
      "title": "Legacy H+M3x2+F (0x63)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x63: header=True, footer=True, left=False, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 99,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 611,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 611,
      "hex": "0x0263",
      "slug": "legacy-63-mobile",
      "title": "Mobile stack for legacy 0x63",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x63. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 99,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 99
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 100,
      "hex": "0x0064",
      "slug": "legacy-64",
      "title": "Legacy L+M3x2 (0x64)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x64: header=False, footer=False, left=True, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 100,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 612,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 612,
      "hex": "0x0264",
      "slug": "legacy-64-mobile",
      "title": "Mobile stack for legacy 0x64",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x64. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 100,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 100
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 101,
      "hex": "0x0065",
      "slug": "legacy-65",
      "title": "Legacy H+L+M3x2 (0x65)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x65: header=True, footer=False, left=True, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 101,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 613,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 613,
      "hex": "0x0265",
      "slug": "legacy-65-mobile",
      "title": "Mobile stack for legacy 0x65",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x65. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 101,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 101
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 102,
      "hex": "0x0066",
      "slug": "legacy-66",
      "title": "Legacy L+M3x2+F (0x66)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x66: header=False, footer=True, left=True, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 102,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 614,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 614,
      "hex": "0x0266",
      "slug": "legacy-66-mobile",
      "title": "Mobile stack for legacy 0x66",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x66. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 102,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 102
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 103,
      "hex": "0x0067",
      "slug": "legacy-67",
      "title": "Legacy H+L+M3x2+F (0x67)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x67: header=True, footer=True, left=True, right=False, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 103,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 615,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 615,
      "hex": "0x0267",
      "slug": "legacy-67-mobile",
      "title": "Mobile stack for legacy 0x67",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x67. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 103,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 103
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 104,
      "hex": "0x0068",
      "slug": "legacy-68",
      "title": "Legacy M3x2+R (0x68)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x68: header=False, footer=False, left=False, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m3x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 104,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 616,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 616,
      "hex": "0x0268",
      "slug": "legacy-68-mobile",
      "title": "Mobile stack for legacy 0x68",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x68. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 104,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 104
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 105,
      "hex": "0x0069",
      "slug": "legacy-69",
      "title": "Legacy H+M3x2+R (0x69)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x69: header=True, footer=False, left=False, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 105,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 617,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 617,
      "hex": "0x0269",
      "slug": "legacy-69-mobile",
      "title": "Mobile stack for legacy 0x69",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x69. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 105,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 105
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 106,
      "hex": "0x006A",
      "slug": "legacy-6a",
      "title": "Legacy M3x2+R+F (0x6A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x6A: header=False, footer=True, left=False, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m3x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 106,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 618,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 618,
      "hex": "0x026A",
      "slug": "legacy-6a-mobile",
      "title": "Mobile stack for legacy 0x6A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x6A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 106,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 106
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 107,
      "hex": "0x006B",
      "slug": "legacy-6b",
      "title": "Legacy H+M3x2+R+F (0x6B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x6B: header=True, footer=True, left=False, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 107,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 619,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 619,
      "hex": "0x026B",
      "slug": "legacy-6b-mobile",
      "title": "Mobile stack for legacy 0x6B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x6B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 107,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 107
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 108,
      "hex": "0x006C",
      "slug": "legacy-6c",
      "title": "Legacy L+M3x2+R (0x6C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x6C: header=False, footer=False, left=True, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 108,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 620,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 620,
      "hex": "0x026C",
      "slug": "legacy-6c-mobile",
      "title": "Mobile stack for legacy 0x6C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x6C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 108,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 108
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 109,
      "hex": "0x006D",
      "slug": "legacy-6d",
      "title": "Legacy H+L+M3x2+R (0x6D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x6D: header=True, footer=False, left=True, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 109,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 621,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 621,
      "hex": "0x026D",
      "slug": "legacy-6d-mobile",
      "title": "Mobile stack for legacy 0x6D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x6D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 109,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 109
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 110,
      "hex": "0x006E",
      "slug": "legacy-6e",
      "title": "Legacy L+M3x2+R+F (0x6E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x6E: header=False, footer=True, left=True, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 110,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 622,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 622,
      "hex": "0x026E",
      "slug": "legacy-6e-mobile",
      "title": "Mobile stack for legacy 0x6E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x6E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 110,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 110
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 111,
      "hex": "0x006F",
      "slug": "legacy-6f",
      "title": "Legacy H+L+M3x2+R+F (0x6F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x6F: header=True, footer=True, left=True, right=True, main=3\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 111,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 623,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 623,
      "hex": "0x026F",
      "slug": "legacy-6f-mobile",
      "title": "Mobile stack for legacy 0x6F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x6F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 111,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 111
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 112,
      "hex": "0x0070",
      "slug": "legacy-70",
      "title": "Legacy M4x2 (0x70)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x70: header=False, footer=False, left=False, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m4x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 112,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 624,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 624,
      "hex": "0x0270",
      "slug": "legacy-70-mobile",
      "title": "Mobile stack for legacy 0x70",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x70. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 112,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 112
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 113,
      "hex": "0x0071",
      "slug": "legacy-71",
      "title": "Legacy H+M4x2 (0x71)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x71: header=True, footer=False, left=False, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 113,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 625,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 625,
      "hex": "0x0271",
      "slug": "legacy-71-mobile",
      "title": "Mobile stack for legacy 0x71",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x71. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 113,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 113
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 114,
      "hex": "0x0072",
      "slug": "legacy-72",
      "title": "Legacy M4x2+F (0x72)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x72: header=False, footer=True, left=False, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m4x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 114,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 626,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 626,
      "hex": "0x0272",
      "slug": "legacy-72-mobile",
      "title": "Mobile stack for legacy 0x72",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x72. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 114,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 114
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 115,
      "hex": "0x0073",
      "slug": "legacy-73",
      "title": "Legacy H+M4x2+F (0x73)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x73: header=True, footer=True, left=False, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 115,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 627,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 627,
      "hex": "0x0273",
      "slug": "legacy-73-mobile",
      "title": "Mobile stack for legacy 0x73",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x73. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 115,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 115
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 116,
      "hex": "0x0074",
      "slug": "legacy-74",
      "title": "Legacy L+M4x2 (0x74)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x74: header=False, footer=False, left=True, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 116,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 628,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 628,
      "hex": "0x0274",
      "slug": "legacy-74-mobile",
      "title": "Mobile stack for legacy 0x74",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x74. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 116,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 116
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 117,
      "hex": "0x0075",
      "slug": "legacy-75",
      "title": "Legacy H+L+M4x2 (0x75)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x75: header=True, footer=False, left=True, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x2"
      ],
      "viewport": "desktop",
      "legacy_byte": 117,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 629,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 629,
      "hex": "0x0275",
      "slug": "legacy-75-mobile",
      "title": "Mobile stack for legacy 0x75",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x75. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 117,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 117
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 118,
      "hex": "0x0076",
      "slug": "legacy-76",
      "title": "Legacy L+M4x2+F (0x76)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x76: header=False, footer=True, left=True, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 118,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 630,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 630,
      "hex": "0x0276",
      "slug": "legacy-76-mobile",
      "title": "Mobile stack for legacy 0x76",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x76. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 118,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 118
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 119,
      "hex": "0x0077",
      "slug": "legacy-77",
      "title": "Legacy H+L+M4x2+F (0x77)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x77: header=True, footer=True, left=True, right=False, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x2+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 119,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 631,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 631,
      "hex": "0x0277",
      "slug": "legacy-77-mobile",
      "title": "Mobile stack for legacy 0x77",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x77. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 119,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 119
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 120,
      "hex": "0x0078",
      "slug": "legacy-78",
      "title": "Legacy M4x2+R (0x78)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x78: header=False, footer=False, left=False, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m4x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 120,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 632,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 632,
      "hex": "0x0278",
      "slug": "legacy-78-mobile",
      "title": "Mobile stack for legacy 0x78",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x78. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 120,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 120
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 121,
      "hex": "0x0079",
      "slug": "legacy-79",
      "title": "Legacy H+M4x2+R (0x79)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x79: header=True, footer=False, left=False, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 121,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 633,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 633,
      "hex": "0x0279",
      "slug": "legacy-79-mobile",
      "title": "Mobile stack for legacy 0x79",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x79. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 121,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 121
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 122,
      "hex": "0x007A",
      "slug": "legacy-7a",
      "title": "Legacy M4x2+R+F (0x7A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x7A: header=False, footer=True, left=False, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "m4x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 122,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 634,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 634,
      "hex": "0x027A",
      "slug": "legacy-7a-mobile",
      "title": "Mobile stack for legacy 0x7A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x7A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 122,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 122
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 123,
      "hex": "0x007B",
      "slug": "legacy-7b",
      "title": "Legacy H+M4x2+R+F (0x7B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x7B: header=True, footer=True, left=False, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 123,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 635,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 635,
      "hex": "0x027B",
      "slug": "legacy-7b-mobile",
      "title": "Mobile stack for legacy 0x7B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x7B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 123,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 123
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 124,
      "hex": "0x007C",
      "slug": "legacy-7c",
      "title": "Legacy L+M4x2+R (0x7C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x7C: header=False, footer=False, left=True, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 124,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 636,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 636,
      "hex": "0x027C",
      "slug": "legacy-7c-mobile",
      "title": "Mobile stack for legacy 0x7C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x7C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 124,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 124
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 125,
      "hex": "0x007D",
      "slug": "legacy-7d",
      "title": "Legacy H+L+M4x2+R (0x7D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x7D: header=True, footer=False, left=True, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x2+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 125,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 637,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 637,
      "hex": "0x027D",
      "slug": "legacy-7d-mobile",
      "title": "Mobile stack for legacy 0x7D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x7D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 125,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 125
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 126,
      "hex": "0x007E",
      "slug": "legacy-7e",
      "title": "Legacy L+M4x2+R+F (0x7E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x7E: header=False, footer=True, left=True, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 126,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 638,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 638,
      "hex": "0x027E",
      "slug": "legacy-7e-mobile",
      "title": "Mobile stack for legacy 0x7E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x7E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 126,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 126
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 127,
      "hex": "0x007F",
      "slug": "legacy-7f",
      "title": "Legacy H+L+M4x2+R+F (0x7F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x7F: header=True, footer=True, left=True, right=True, main=4\u00d72.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x2+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 127,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 639,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 639,
      "hex": "0x027F",
      "slug": "legacy-7f-mobile",
      "title": "Mobile stack for legacy 0x7F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x7F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 127,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 127
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 128,
      "hex": "0x0080",
      "slug": "legacy-80",
      "title": "Legacy M1x3 (0x80)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x80: header=False, footer=False, left=False, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m1x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 128,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 640,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 640,
      "hex": "0x0280",
      "slug": "legacy-80-mobile",
      "title": "Mobile stack for legacy 0x80",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x80. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 128,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 128
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 129,
      "hex": "0x0081",
      "slug": "legacy-81",
      "title": "Legacy H+M1x3 (0x81)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x81: header=True, footer=False, left=False, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 129,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 641,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 641,
      "hex": "0x0281",
      "slug": "legacy-81-mobile",
      "title": "Mobile stack for legacy 0x81",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x81. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 129,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 129
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 130,
      "hex": "0x0082",
      "slug": "legacy-82",
      "title": "Legacy M1x3+F (0x82)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x82: header=False, footer=True, left=False, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m1x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 130,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 642,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 642,
      "hex": "0x0282",
      "slug": "legacy-82-mobile",
      "title": "Mobile stack for legacy 0x82",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x82. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 130,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 130
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 131,
      "hex": "0x0083",
      "slug": "legacy-83",
      "title": "Legacy H+M1x3+F (0x83)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x83: header=True, footer=True, left=False, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 131,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 643,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 643,
      "hex": "0x0283",
      "slug": "legacy-83-mobile",
      "title": "Mobile stack for legacy 0x83",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x83. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 131,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 131
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 132,
      "hex": "0x0084",
      "slug": "legacy-84",
      "title": "Legacy L+M1x3 (0x84)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x84: header=False, footer=False, left=True, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 132,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 644,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 644,
      "hex": "0x0284",
      "slug": "legacy-84-mobile",
      "title": "Mobile stack for legacy 0x84",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x84. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 132,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 132
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 133,
      "hex": "0x0085",
      "slug": "legacy-85",
      "title": "Legacy H+L+M1x3 (0x85)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x85: header=True, footer=False, left=True, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 133,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 645,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 645,
      "hex": "0x0285",
      "slug": "legacy-85-mobile",
      "title": "Mobile stack for legacy 0x85",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x85. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 133,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 133
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 134,
      "hex": "0x0086",
      "slug": "legacy-86",
      "title": "Legacy L+M1x3+F (0x86)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x86: header=False, footer=True, left=True, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 134,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 646,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 646,
      "hex": "0x0286",
      "slug": "legacy-86-mobile",
      "title": "Mobile stack for legacy 0x86",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x86. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 134,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 134
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 135,
      "hex": "0x0087",
      "slug": "legacy-87",
      "title": "Legacy H+L+M1x3+F (0x87)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x87: header=True, footer=True, left=True, right=False, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 135,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 647,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 647,
      "hex": "0x0287",
      "slug": "legacy-87-mobile",
      "title": "Mobile stack for legacy 0x87",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x87. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 135,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 135
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 136,
      "hex": "0x0088",
      "slug": "legacy-88",
      "title": "Legacy M1x3+R (0x88)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x88: header=False, footer=False, left=False, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m1x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 136,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 648,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 648,
      "hex": "0x0288",
      "slug": "legacy-88-mobile",
      "title": "Mobile stack for legacy 0x88",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x88. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 136,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 136
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 137,
      "hex": "0x0089",
      "slug": "legacy-89",
      "title": "Legacy H+M1x3+R (0x89)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x89: header=True, footer=False, left=False, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 137,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 649,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 649,
      "hex": "0x0289",
      "slug": "legacy-89-mobile",
      "title": "Mobile stack for legacy 0x89",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x89. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 137,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 137
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 138,
      "hex": "0x008A",
      "slug": "legacy-8a",
      "title": "Legacy M1x3+R+F (0x8A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x8A: header=False, footer=True, left=False, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m1x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 138,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 650,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 650,
      "hex": "0x028A",
      "slug": "legacy-8a-mobile",
      "title": "Mobile stack for legacy 0x8A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x8A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 138,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 138
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 139,
      "hex": "0x008B",
      "slug": "legacy-8b",
      "title": "Legacy H+M1x3+R+F (0x8B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x8B: header=True, footer=True, left=False, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 139,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 651,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 651,
      "hex": "0x028B",
      "slug": "legacy-8b-mobile",
      "title": "Mobile stack for legacy 0x8B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x8B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 139,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 139
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 140,
      "hex": "0x008C",
      "slug": "legacy-8c",
      "title": "Legacy L+M1x3+R (0x8C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x8C: header=False, footer=False, left=True, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 140,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 652,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 652,
      "hex": "0x028C",
      "slug": "legacy-8c-mobile",
      "title": "Mobile stack for legacy 0x8C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x8C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 140,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 140
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 141,
      "hex": "0x008D",
      "slug": "legacy-8d",
      "title": "Legacy H+L+M1x3+R (0x8D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x8D: header=True, footer=False, left=True, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 141,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 653,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 653,
      "hex": "0x028D",
      "slug": "legacy-8d-mobile",
      "title": "Mobile stack for legacy 0x8D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x8D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 141,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 141
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 142,
      "hex": "0x008E",
      "slug": "legacy-8e",
      "title": "Legacy L+M1x3+R+F (0x8E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x8E: header=False, footer=True, left=True, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 142,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 654,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 654,
      "hex": "0x028E",
      "slug": "legacy-8e-mobile",
      "title": "Mobile stack for legacy 0x8E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x8E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 142,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "left",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 142
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 143,
      "hex": "0x008F",
      "slug": "legacy-8f",
      "title": "Legacy H+L+M1x3+R+F (0x8F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x8F: header=True, footer=True, left=True, right=True, main=1\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 143,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 655,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 655,
      "hex": "0x028F",
      "slug": "legacy-8f-mobile",
      "title": "Mobile stack for legacy 0x8F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x8F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 143,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 143
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 144,
      "hex": "0x0090",
      "slug": "legacy-90",
      "title": "Legacy M2x3 (0x90)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x90: header=False, footer=False, left=False, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m2x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 144,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 656,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 656,
      "hex": "0x0290",
      "slug": "legacy-90-mobile",
      "title": "Mobile stack for legacy 0x90",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x90. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 144,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 144
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 145,
      "hex": "0x0091",
      "slug": "legacy-91",
      "title": "Legacy H+M2x3 (0x91)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x91: header=True, footer=False, left=False, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 145,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 657,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 657,
      "hex": "0x0291",
      "slug": "legacy-91-mobile",
      "title": "Mobile stack for legacy 0x91",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x91. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 145,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 145
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 146,
      "hex": "0x0092",
      "slug": "legacy-92",
      "title": "Legacy M2x3+F (0x92)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x92: header=False, footer=True, left=False, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m2x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 146,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 658,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 658,
      "hex": "0x0292",
      "slug": "legacy-92-mobile",
      "title": "Mobile stack for legacy 0x92",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x92. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 146,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 146
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 147,
      "hex": "0x0093",
      "slug": "legacy-93",
      "title": "Legacy H+M2x3+F (0x93)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x93: header=True, footer=True, left=False, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 147,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 659,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 659,
      "hex": "0x0293",
      "slug": "legacy-93-mobile",
      "title": "Mobile stack for legacy 0x93",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x93. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 147,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 147
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 148,
      "hex": "0x0094",
      "slug": "legacy-94",
      "title": "Legacy L+M2x3 (0x94)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x94: header=False, footer=False, left=True, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 148,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 660,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 660,
      "hex": "0x0294",
      "slug": "legacy-94-mobile",
      "title": "Mobile stack for legacy 0x94",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x94. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 148,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 148
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 149,
      "hex": "0x0095",
      "slug": "legacy-95",
      "title": "Legacy H+L+M2x3 (0x95)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x95: header=True, footer=False, left=True, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 149,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 661,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 661,
      "hex": "0x0295",
      "slug": "legacy-95-mobile",
      "title": "Mobile stack for legacy 0x95",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x95. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 149,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 149
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 150,
      "hex": "0x0096",
      "slug": "legacy-96",
      "title": "Legacy L+M2x3+F (0x96)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x96: header=False, footer=True, left=True, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 150,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 662,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 662,
      "hex": "0x0296",
      "slug": "legacy-96-mobile",
      "title": "Mobile stack for legacy 0x96",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x96. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 150,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 150
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 151,
      "hex": "0x0097",
      "slug": "legacy-97",
      "title": "Legacy H+L+M2x3+F (0x97)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x97: header=True, footer=True, left=True, right=False, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 151,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 663,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 663,
      "hex": "0x0297",
      "slug": "legacy-97-mobile",
      "title": "Mobile stack for legacy 0x97",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x97. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 151,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 151
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 152,
      "hex": "0x0098",
      "slug": "legacy-98",
      "title": "Legacy M2x3+R (0x98)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x98: header=False, footer=False, left=False, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m2x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 152,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 664,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 664,
      "hex": "0x0298",
      "slug": "legacy-98-mobile",
      "title": "Mobile stack for legacy 0x98",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x98. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 152,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 152
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 153,
      "hex": "0x0099",
      "slug": "legacy-99",
      "title": "Legacy H+M2x3+R (0x99)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x99: header=True, footer=False, left=False, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 153,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 665,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 665,
      "hex": "0x0299",
      "slug": "legacy-99-mobile",
      "title": "Mobile stack for legacy 0x99",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x99. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 153,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 153
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 154,
      "hex": "0x009A",
      "slug": "legacy-9a",
      "title": "Legacy M2x3+R+F (0x9A)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x9A: header=False, footer=True, left=False, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m2x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 154,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 666,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 666,
      "hex": "0x029A",
      "slug": "legacy-9a-mobile",
      "title": "Mobile stack for legacy 0x9A",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x9A. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 154,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 154
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 155,
      "hex": "0x009B",
      "slug": "legacy-9b",
      "title": "Legacy H+M2x3+R+F (0x9B)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x9B: header=True, footer=True, left=False, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 155,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 667,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 667,
      "hex": "0x029B",
      "slug": "legacy-9b-mobile",
      "title": "Mobile stack for legacy 0x9B",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x9B. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 155,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 155
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 156,
      "hex": "0x009C",
      "slug": "legacy-9c",
      "title": "Legacy L+M2x3+R (0x9C)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x9C: header=False, footer=False, left=True, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 156,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 668,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 668,
      "hex": "0x029C",
      "slug": "legacy-9c-mobile",
      "title": "Mobile stack for legacy 0x9C",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x9C. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 156,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 156
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 157,
      "hex": "0x009D",
      "slug": "legacy-9d",
      "title": "Legacy H+L+M2x3+R (0x9D)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x9D: header=True, footer=False, left=True, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 157,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 669,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 669,
      "hex": "0x029D",
      "slug": "legacy-9d-mobile",
      "title": "Mobile stack for legacy 0x9D",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x9D. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 157,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 157
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 158,
      "hex": "0x009E",
      "slug": "legacy-9e",
      "title": "Legacy L+M2x3+R+F (0x9E)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x9E: header=False, footer=True, left=True, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 158,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 670,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 670,
      "hex": "0x029E",
      "slug": "legacy-9e-mobile",
      "title": "Mobile stack for legacy 0x9E",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x9E. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 158,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "left",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 7,
          "role": "right",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 158
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 159,
      "hex": "0x009F",
      "slug": "legacy-9f",
      "title": "Legacy H+L+M2x3+R+F (0x9F)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0x9F: header=True, footer=True, left=True, right=True, main=2\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 159,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 671,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 671,
      "hex": "0x029F",
      "slug": "legacy-9f-mobile",
      "title": "Mobile stack for legacy 0x9F",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0x9F. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 159,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "left",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 159
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 160,
      "hex": "0x00A0",
      "slug": "legacy-a0",
      "title": "Legacy M3x3 (0xA0)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA0: header=False, footer=False, left=False, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m3x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 160,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 672,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 672,
      "hex": "0x02A0",
      "slug": "legacy-a0-mobile",
      "title": "Mobile stack for legacy 0xA0",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA0. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 160,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 160
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 161,
      "hex": "0x00A1",
      "slug": "legacy-a1",
      "title": "Legacy H+M3x3 (0xA1)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA1: header=True, footer=False, left=False, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 161,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 673,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 673,
      "hex": "0x02A1",
      "slug": "legacy-a1-mobile",
      "title": "Mobile stack for legacy 0xA1",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA1. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 161,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 161
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 162,
      "hex": "0x00A2",
      "slug": "legacy-a2",
      "title": "Legacy M3x3+F (0xA2)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA2: header=False, footer=True, left=False, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m3x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 162,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 674,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 674,
      "hex": "0x02A2",
      "slug": "legacy-a2-mobile",
      "title": "Mobile stack for legacy 0xA2",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA2. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 162,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 162
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 163,
      "hex": "0x00A3",
      "slug": "legacy-a3",
      "title": "Legacy H+M3x3+F (0xA3)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA3: header=True, footer=True, left=False, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 163,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 675,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 675,
      "hex": "0x02A3",
      "slug": "legacy-a3-mobile",
      "title": "Mobile stack for legacy 0xA3",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA3. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 163,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 163
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 164,
      "hex": "0x00A4",
      "slug": "legacy-a4",
      "title": "Legacy L+M3x3 (0xA4)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA4: header=False, footer=False, left=True, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 164,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 676,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 676,
      "hex": "0x02A4",
      "slug": "legacy-a4-mobile",
      "title": "Mobile stack for legacy 0xA4",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA4. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 164,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 164
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 165,
      "hex": "0x00A5",
      "slug": "legacy-a5",
      "title": "Legacy H+L+M3x3 (0xA5)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA5: header=True, footer=False, left=True, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 165,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 677,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 677,
      "hex": "0x02A5",
      "slug": "legacy-a5-mobile",
      "title": "Mobile stack for legacy 0xA5",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA5. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 165,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "left",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 165
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 166,
      "hex": "0x00A6",
      "slug": "legacy-a6",
      "title": "Legacy L+M3x3+F (0xA6)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA6: header=False, footer=True, left=True, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 166,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 678,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 678,
      "hex": "0x02A6",
      "slug": "legacy-a6-mobile",
      "title": "Mobile stack for legacy 0xA6",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA6. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 166,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 166
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 167,
      "hex": "0x00A7",
      "slug": "legacy-a7",
      "title": "Legacy H+L+M3x3+F (0xA7)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA7: header=True, footer=True, left=True, right=False, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 167,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 679,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 679,
      "hex": "0x02A7",
      "slug": "legacy-a7-mobile",
      "title": "Mobile stack for legacy 0xA7",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA7. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 167,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "left",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 167
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 168,
      "hex": "0x00A8",
      "slug": "legacy-a8",
      "title": "Legacy M3x3+R (0xA8)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA8: header=False, footer=False, left=False, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m3x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 168,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 680,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 680,
      "hex": "0x02A8",
      "slug": "legacy-a8-mobile",
      "title": "Mobile stack for legacy 0xA8",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA8. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 168,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 168
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 169,
      "hex": "0x00A9",
      "slug": "legacy-a9",
      "title": "Legacy H+M3x3+R (0xA9)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xA9: header=True, footer=False, left=False, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 169,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 681,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 681,
      "hex": "0x02A9",
      "slug": "legacy-a9-mobile",
      "title": "Mobile stack for legacy 0xA9",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xA9. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 169,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 169
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 170,
      "hex": "0x00AA",
      "slug": "legacy-aa",
      "title": "Legacy M3x3+R+F (0xAA)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xAA: header=False, footer=True, left=False, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m3x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 170,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 682,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 682,
      "hex": "0x02AA",
      "slug": "legacy-aa-mobile",
      "title": "Mobile stack for legacy 0xAA",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xAA. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 170,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 170
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 171,
      "hex": "0x00AB",
      "slug": "legacy-ab",
      "title": "Legacy H+M3x3+R+F (0xAB)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xAB: header=True, footer=True, left=False, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 171,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 683,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 683,
      "hex": "0x02AB",
      "slug": "legacy-ab-mobile",
      "title": "Mobile stack for legacy 0xAB",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xAB. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 171,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 171
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 172,
      "hex": "0x00AC",
      "slug": "legacy-ac",
      "title": "Legacy L+M3x3+R (0xAC)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xAC: header=False, footer=False, left=True, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 172,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 684,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 684,
      "hex": "0x02AC",
      "slug": "legacy-ac-mobile",
      "title": "Mobile stack for legacy 0xAC",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xAC. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 172,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 172
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 173,
      "hex": "0x00AD",
      "slug": "legacy-ad",
      "title": "Legacy H+L+M3x3+R (0xAD)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xAD: header=True, footer=False, left=True, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 173,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 685,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 685,
      "hex": "0x02AD",
      "slug": "legacy-ad-mobile",
      "title": "Mobile stack for legacy 0xAD",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xAD. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 173,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "left",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 11,
          "role": "right",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 173
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 174,
      "hex": "0x00AE",
      "slug": "legacy-ae",
      "title": "Legacy L+M3x3+R+F (0xAE)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xAE: header=False, footer=True, left=True, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 174,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 686,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 686,
      "hex": "0x02AE",
      "slug": "legacy-ae-mobile",
      "title": "Mobile stack for legacy 0xAE",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xAE. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 174,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 174
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 175,
      "hex": "0x00AF",
      "slug": "legacy-af",
      "title": "Legacy H+L+M3x3+R+F (0xAF)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xAF: header=True, footer=True, left=True, right=True, main=3\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 175,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 12,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 687,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 687,
      "hex": "0x02AF",
      "slug": "legacy-af-mobile",
      "title": "Mobile stack for legacy 0xAF",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xAF. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 175,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "left",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 11,
          "role": "right",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 12,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 175
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 176,
      "hex": "0x00B0",
      "slug": "legacy-b0",
      "title": "Legacy M4x3 (0xB0)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB0: header=False, footer=False, left=False, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m4x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 176,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 688,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 688,
      "hex": "0x02B0",
      "slug": "legacy-b0-mobile",
      "title": "Mobile stack for legacy 0xB0",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB0. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 176,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 176
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 177,
      "hex": "0x00B1",
      "slug": "legacy-b1",
      "title": "Legacy H+M4x3 (0xB1)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB1: header=True, footer=False, left=False, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 177,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 689,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 689,
      "hex": "0x02B1",
      "slug": "legacy-b1-mobile",
      "title": "Mobile stack for legacy 0xB1",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB1. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 177,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 177
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 178,
      "hex": "0x00B2",
      "slug": "legacy-b2",
      "title": "Legacy M4x3+F (0xB2)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB2: header=False, footer=True, left=False, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m4x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 178,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 690,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 690,
      "hex": "0x02B2",
      "slug": "legacy-b2-mobile",
      "title": "Mobile stack for legacy 0xB2",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB2. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 178,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 178
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 179,
      "hex": "0x00B3",
      "slug": "legacy-b3",
      "title": "Legacy H+M4x3+F (0xB3)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB3: header=True, footer=True, left=False, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 179,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 691,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 691,
      "hex": "0x02B3",
      "slug": "legacy-b3-mobile",
      "title": "Mobile stack for legacy 0xB3",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB3. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 179,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 179
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 180,
      "hex": "0x00B4",
      "slug": "legacy-b4",
      "title": "Legacy L+M4x3 (0xB4)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB4: header=False, footer=False, left=True, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 180,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
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          "default_width_pct": 25,
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          "default_margin_pct": [
            0,
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            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
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            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
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            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 692,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 692,
      "hex": "0x02B4",
      "slug": "legacy-b4-mobile",
      "title": "Mobile stack for legacy 0xB4",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB4. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 180,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
            0,
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            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
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          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
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            0,
            0
          ],
          "default_padding_pct": [
            2,
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            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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        },
        {
          "index": 3,
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          "default_width_pct": 100,
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            0
          ],
          "default_padding_pct": [
            2,
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
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        },
        {
          "index": 4,
          "role": "main",
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          "full_height_top": false,
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            "text",
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        },
        {
          "index": 5,
          "role": "main",
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
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          "full_height_top": false,
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          "default_width_pct": 100,
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          "default_margin_pct": [
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            0
          ],
          "default_padding_pct": [
            2,
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            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
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          "grid_row": 7,
          "full_height_top": false,
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          "default_margin_pct": [
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            0,
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          ],
          "default_padding_pct": [
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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        },
        {
          "index": 8,
          "role": "main",
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          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
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            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
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          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 180
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 181,
      "hex": "0x00B5",
      "slug": "legacy-b5",
      "title": "Legacy H+L+M4x3 (0xB5)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB5: header=True, footer=False, left=True, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x3"
      ],
      "viewport": "desktop",
      "legacy_byte": 181,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 693,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 693,
      "hex": "0x02B5",
      "slug": "legacy-b5-mobile",
      "title": "Mobile stack for legacy 0xB5",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB5. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 181,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 181
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 182,
      "hex": "0x00B6",
      "slug": "legacy-b6",
      "title": "Legacy L+M4x3+F (0xB6)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB6: header=False, footer=True, left=True, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 182,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 694,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 694,
      "hex": "0x02B6",
      "slug": "legacy-b6-mobile",
      "title": "Mobile stack for legacy 0xB6",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB6. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 182,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 182
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 183,
      "hex": "0x00B7",
      "slug": "legacy-b7",
      "title": "Legacy H+L+M4x3+F (0xB7)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB7: header=True, footer=True, left=True, right=False, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x3+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 183,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 695,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 695,
      "hex": "0x02B7",
      "slug": "legacy-b7-mobile",
      "title": "Mobile stack for legacy 0xB7",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB7. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 183,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 183
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 184,
      "hex": "0x00B8",
      "slug": "legacy-b8",
      "title": "Legacy M4x3+R (0xB8)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB8: header=False, footer=False, left=False, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m4x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 184,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 696,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 696,
      "hex": "0x02B8",
      "slug": "legacy-b8-mobile",
      "title": "Mobile stack for legacy 0xB8",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB8. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 184,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 184
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 185,
      "hex": "0x00B9",
      "slug": "legacy-b9",
      "title": "Legacy H+M4x3+R (0xB9)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xB9: header=True, footer=False, left=False, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 185,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 697,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 697,
      "hex": "0x02B9",
      "slug": "legacy-b9-mobile",
      "title": "Mobile stack for legacy 0xB9",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xB9. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 185,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 185
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 186,
      "hex": "0x00BA",
      "slug": "legacy-ba",
      "title": "Legacy M4x3+R+F (0xBA)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xBA: header=False, footer=True, left=False, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "m4x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 186,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 698,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 698,
      "hex": "0x02BA",
      "slug": "legacy-ba-mobile",
      "title": "Mobile stack for legacy 0xBA",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xBA. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 186,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 186
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 187,
      "hex": "0x00BB",
      "slug": "legacy-bb",
      "title": "Legacy H+M4x3+R+F (0xBB)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xBB: header=True, footer=True, left=False, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 187,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 699,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 699,
      "hex": "0x02BB",
      "slug": "legacy-bb-mobile",
      "title": "Mobile stack for legacy 0xBB",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xBB. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 187,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 187
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 188,
      "hex": "0x00BC",
      "slug": "legacy-bc",
      "title": "Legacy L+M4x3+R (0xBC)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xBC: header=False, footer=False, left=True, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 188,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 700,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 700,
      "hex": "0x02BC",
      "slug": "legacy-bc-mobile",
      "title": "Mobile stack for legacy 0xBC",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xBC. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 188,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 188
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 189,
      "hex": "0x00BD",
      "slug": "legacy-bd",
      "title": "Legacy H+L+M4x3+R (0xBD)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xBD: header=True, footer=False, left=True, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x3+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 189,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 701,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 701,
      "hex": "0x02BD",
      "slug": "legacy-bd-mobile",
      "title": "Mobile stack for legacy 0xBD",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xBD. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 189,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 189
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 190,
      "hex": "0x00BE",
      "slug": "legacy-be",
      "title": "Legacy L+M4x3+R+F (0xBE)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xBE: header=False, footer=True, left=True, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 190,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 702,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 702,
      "hex": "0x02BE",
      "slug": "legacy-be-mobile",
      "title": "Mobile stack for legacy 0xBE",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xBE. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 190,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 190
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 191,
      "hex": "0x00BF",
      "slug": "legacy-bf",
      "title": "Legacy H+L+M4x3+R+F (0xBF)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xBF: header=True, footer=True, left=True, right=True, main=4\u00d73.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x3+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 191,
      "pane_count": 16,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 15,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 703,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 703,
      "hex": "0x02BF",
      "slug": "legacy-bf-mobile",
      "title": "Mobile stack for legacy 0xBF",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xBF. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 191,
      "pane_count": 16,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 15,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 191
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 192,
      "hex": "0x00C0",
      "slug": "legacy-c0",
      "title": "Legacy M1x4 (0xC0)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC0: header=False, footer=False, left=False, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m1x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 192,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 704,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 704,
      "hex": "0x02C0",
      "slug": "legacy-c0-mobile",
      "title": "Mobile stack for legacy 0xC0",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC0. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 192,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 192
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 193,
      "hex": "0x00C1",
      "slug": "legacy-c1",
      "title": "Legacy H+M1x4 (0xC1)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC1: header=True, footer=False, left=False, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 193,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 705,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 705,
      "hex": "0x02C1",
      "slug": "legacy-c1-mobile",
      "title": "Mobile stack for legacy 0xC1",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC1. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 193,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 193
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 194,
      "hex": "0x00C2",
      "slug": "legacy-c2",
      "title": "Legacy M1x4+F (0xC2)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC2: header=False, footer=True, left=False, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m1x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 194,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 706,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 706,
      "hex": "0x02C2",
      "slug": "legacy-c2-mobile",
      "title": "Mobile stack for legacy 0xC2",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC2. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 194,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 194
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 195,
      "hex": "0x00C3",
      "slug": "legacy-c3",
      "title": "Legacy H+M1x4+F (0xC3)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC3: header=True, footer=True, left=False, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 195,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 707,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 707,
      "hex": "0x02C3",
      "slug": "legacy-c3-mobile",
      "title": "Mobile stack for legacy 0xC3",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC3. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 195,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 195
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 196,
      "hex": "0x00C4",
      "slug": "legacy-c4",
      "title": "Legacy L+M1x4 (0xC4)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC4: header=False, footer=False, left=True, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 196,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 708,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 708,
      "hex": "0x02C4",
      "slug": "legacy-c4-mobile",
      "title": "Mobile stack for legacy 0xC4",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC4. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 196,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 196
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 197,
      "hex": "0x00C5",
      "slug": "legacy-c5",
      "title": "Legacy H+L+M1x4 (0xC5)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC5: header=True, footer=False, left=True, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 197,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 709,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 709,
      "hex": "0x02C5",
      "slug": "legacy-c5-mobile",
      "title": "Mobile stack for legacy 0xC5",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC5. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 197,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 197
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 198,
      "hex": "0x00C6",
      "slug": "legacy-c6",
      "title": "Legacy L+M1x4+F (0xC6)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC6: header=False, footer=True, left=True, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 198,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 710,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 710,
      "hex": "0x02C6",
      "slug": "legacy-c6-mobile",
      "title": "Mobile stack for legacy 0xC6",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC6. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 198,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 198
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 199,
      "hex": "0x00C7",
      "slug": "legacy-c7",
      "title": "Legacy H+L+M1x4+F (0xC7)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC7: header=True, footer=True, left=True, right=False, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 199,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 711,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 711,
      "hex": "0x02C7",
      "slug": "legacy-c7-mobile",
      "title": "Mobile stack for legacy 0xC7",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC7. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 199,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 199
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 200,
      "hex": "0x00C8",
      "slug": "legacy-c8",
      "title": "Legacy M1x4+R (0xC8)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC8: header=False, footer=False, left=False, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m1x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 200,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 712,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 712,
      "hex": "0x02C8",
      "slug": "legacy-c8-mobile",
      "title": "Mobile stack for legacy 0xC8",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC8. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 200,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 200
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 201,
      "hex": "0x00C9",
      "slug": "legacy-c9",
      "title": "Legacy H+M1x4+R (0xC9)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xC9: header=True, footer=False, left=False, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 201,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 713,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 713,
      "hex": "0x02C9",
      "slug": "legacy-c9-mobile",
      "title": "Mobile stack for legacy 0xC9",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xC9. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 201,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 201
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 202,
      "hex": "0x00CA",
      "slug": "legacy-ca",
      "title": "Legacy M1x4+R+F (0xCA)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xCA: header=False, footer=True, left=False, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m1x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 202,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 714,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 714,
      "hex": "0x02CA",
      "slug": "legacy-ca-mobile",
      "title": "Mobile stack for legacy 0xCA",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xCA. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 202,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "right",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 202
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 203,
      "hex": "0x00CB",
      "slug": "legacy-cb",
      "title": "Legacy H+M1x4+R+F (0xCB)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xCB: header=True, footer=True, left=False, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m1x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 203,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 715,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 715,
      "hex": "0x02CB",
      "slug": "legacy-cb-mobile",
      "title": "Mobile stack for legacy 0xCB",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xCB. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 203,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 203
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 204,
      "hex": "0x00CC",
      "slug": "legacy-cc",
      "title": "Legacy L+M1x4+R (0xCC)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xCC: header=False, footer=False, left=True, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 204,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 716,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 716,
      "hex": "0x02CC",
      "slug": "legacy-cc-mobile",
      "title": "Mobile stack for legacy 0xCC",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xCC. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 204,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 204
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 205,
      "hex": "0x00CD",
      "slug": "legacy-cd",
      "title": "Legacy H+L+M1x4+R (0xCD)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xCD: header=True, footer=False, left=True, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 205,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 717,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 717,
      "hex": "0x02CD",
      "slug": "legacy-cd-mobile",
      "title": "Mobile stack for legacy 0xCD",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xCD. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 205,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 205
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 206,
      "hex": "0x00CE",
      "slug": "legacy-ce",
      "title": "Legacy L+M1x4+R+F (0xCE)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xCE: header=False, footer=True, left=True, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m1x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 206,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 718,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 718,
      "hex": "0x02CE",
      "slug": "legacy-ce-mobile",
      "title": "Mobile stack for legacy 0xCE",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xCE. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 206,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "left",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 5,
          "role": "right",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 206
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 207,
      "hex": "0x00CF",
      "slug": "legacy-cf",
      "title": "Legacy H+L+M1x4+R+F (0xCF)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xCF: header=True, footer=True, left=True, right=True, main=1\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m1x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 207,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 719,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 719,
      "hex": "0x02CF",
      "slug": "legacy-cf-mobile",
      "title": "Mobile stack for legacy 0xCF",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xCF. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 207,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "left",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 6,
          "role": "right",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 7,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 207
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 208,
      "hex": "0x00D0",
      "slug": "legacy-d0",
      "title": "Legacy M2x4 (0xD0)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD0: header=False, footer=False, left=False, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m2x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 208,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 720,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 720,
      "hex": "0x02D0",
      "slug": "legacy-d0-mobile",
      "title": "Mobile stack for legacy 0xD0",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD0. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 208,
      "pane_count": 8,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 208
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 209,
      "hex": "0x00D1",
      "slug": "legacy-d1",
      "title": "Legacy H+M2x4 (0xD1)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD1: header=True, footer=False, left=False, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 209,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 721,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 721,
      "hex": "0x02D1",
      "slug": "legacy-d1-mobile",
      "title": "Mobile stack for legacy 0xD1",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD1. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 209,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 209
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 210,
      "hex": "0x00D2",
      "slug": "legacy-d2",
      "title": "Legacy M2x4+F (0xD2)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD2: header=False, footer=True, left=False, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m2x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 210,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 722,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 722,
      "hex": "0x02D2",
      "slug": "legacy-d2-mobile",
      "title": "Mobile stack for legacy 0xD2",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD2. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 210,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 210
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 211,
      "hex": "0x00D3",
      "slug": "legacy-d3",
      "title": "Legacy H+M2x4+F (0xD3)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD3: header=True, footer=True, left=False, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 211,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 723,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 723,
      "hex": "0x02D3",
      "slug": "legacy-d3-mobile",
      "title": "Mobile stack for legacy 0xD3",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD3. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 211,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 211
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 212,
      "hex": "0x00D4",
      "slug": "legacy-d4",
      "title": "Legacy L+M2x4 (0xD4)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD4: header=False, footer=False, left=True, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 212,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 724,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 724,
      "hex": "0x02D4",
      "slug": "legacy-d4-mobile",
      "title": "Mobile stack for legacy 0xD4",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD4. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 212,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 212
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 213,
      "hex": "0x00D5",
      "slug": "legacy-d5",
      "title": "Legacy H+L+M2x4 (0xD5)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD5: header=True, footer=False, left=True, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 213,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 725,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 725,
      "hex": "0x02D5",
      "slug": "legacy-d5-mobile",
      "title": "Mobile stack for legacy 0xD5",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD5. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 213,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 213
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 214,
      "hex": "0x00D6",
      "slug": "legacy-d6",
      "title": "Legacy L+M2x4+F (0xD6)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD6: header=False, footer=True, left=True, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 214,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 726,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 726,
      "hex": "0x02D6",
      "slug": "legacy-d6-mobile",
      "title": "Mobile stack for legacy 0xD6",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD6. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 214,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 214
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 215,
      "hex": "0x00D7",
      "slug": "legacy-d7",
      "title": "Legacy H+L+M2x4+F (0xD7)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD7: header=True, footer=True, left=True, right=False, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 215,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 727,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 727,
      "hex": "0x02D7",
      "slug": "legacy-d7-mobile",
      "title": "Mobile stack for legacy 0xD7",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD7. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 215,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 215
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 216,
      "hex": "0x00D8",
      "slug": "legacy-d8",
      "title": "Legacy M2x4+R (0xD8)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD8: header=False, footer=False, left=False, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m2x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 216,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 728,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 728,
      "hex": "0x02D8",
      "slug": "legacy-d8-mobile",
      "title": "Mobile stack for legacy 0xD8",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD8. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 216,
      "pane_count": 9,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 216
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 217,
      "hex": "0x00D9",
      "slug": "legacy-d9",
      "title": "Legacy H+M2x4+R (0xD9)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xD9: header=True, footer=False, left=False, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 217,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 729,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 729,
      "hex": "0x02D9",
      "slug": "legacy-d9-mobile",
      "title": "Mobile stack for legacy 0xD9",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xD9. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 217,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 217
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 218,
      "hex": "0x00DA",
      "slug": "legacy-da",
      "title": "Legacy M2x4+R+F (0xDA)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xDA: header=False, footer=True, left=False, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m2x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 218,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 730,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 730,
      "hex": "0x02DA",
      "slug": "legacy-da-mobile",
      "title": "Mobile stack for legacy 0xDA",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xDA. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 218,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "right",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 9,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 218
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 219,
      "hex": "0x00DB",
      "slug": "legacy-db",
      "title": "Legacy H+M2x4+R+F (0xDB)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xDB: header=True, footer=True, left=False, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m2x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 219,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 731,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 731,
      "hex": "0x02DB",
      "slug": "legacy-db-mobile",
      "title": "Mobile stack for legacy 0xDB",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xDB. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 219,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 219
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 220,
      "hex": "0x00DC",
      "slug": "legacy-dc",
      "title": "Legacy L+M2x4+R (0xDC)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xDC: header=False, footer=False, left=True, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 220,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 732,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 732,
      "hex": "0x02DC",
      "slug": "legacy-dc-mobile",
      "title": "Mobile stack for legacy 0xDC",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xDC. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 220,
      "pane_count": 10,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 220
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 221,
      "hex": "0x00DD",
      "slug": "legacy-dd",
      "title": "Legacy H+L+M2x4+R (0xDD)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xDD: header=True, footer=False, left=True, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 221,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 733,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 733,
      "hex": "0x02DD",
      "slug": "legacy-dd-mobile",
      "title": "Mobile stack for legacy 0xDD",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xDD. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 221,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 221
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 222,
      "hex": "0x00DE",
      "slug": "legacy-de",
      "title": "Legacy L+M2x4+R+F (0xDE)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xDE: header=False, footer=True, left=True, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m2x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 222,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 734,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 734,
      "hex": "0x02DE",
      "slug": "legacy-de-mobile",
      "title": "Mobile stack for legacy 0xDE",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xDE. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 222,
      "pane_count": 11,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "left",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 9,
          "role": "right",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 10,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 222
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 223,
      "hex": "0x00DF",
      "slug": "legacy-df",
      "title": "Legacy H+L+M2x4+R+F (0xDF)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xDF: header=True, footer=True, left=True, right=True, main=2\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m2x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 223,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 735,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 735,
      "hex": "0x02DF",
      "slug": "legacy-df-mobile",
      "title": "Mobile stack for legacy 0xDF",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xDF. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 223,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "left",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 10,
          "role": "right",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 11,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 223
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 224,
      "hex": "0x00E0",
      "slug": "legacy-e0",
      "title": "Legacy M3x4 (0xE0)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE0: header=False, footer=False, left=False, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m3x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 224,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 736,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 736,
      "hex": "0x02E0",
      "slug": "legacy-e0-mobile",
      "title": "Mobile stack for legacy 0xE0",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE0. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 224,
      "pane_count": 12,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 224
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 225,
      "hex": "0x00E1",
      "slug": "legacy-e1",
      "title": "Legacy H+M3x4 (0xE1)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE1: header=True, footer=False, left=False, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 225,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 737,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 737,
      "hex": "0x02E1",
      "slug": "legacy-e1-mobile",
      "title": "Mobile stack for legacy 0xE1",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE1. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 225,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 225
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 226,
      "hex": "0x00E2",
      "slug": "legacy-e2",
      "title": "Legacy M3x4+F (0xE2)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE2: header=False, footer=True, left=False, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m3x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 226,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 738,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 738,
      "hex": "0x02E2",
      "slug": "legacy-e2-mobile",
      "title": "Mobile stack for legacy 0xE2",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE2. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 226,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 226
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 227,
      "hex": "0x00E3",
      "slug": "legacy-e3",
      "title": "Legacy H+M3x4+F (0xE3)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE3: header=True, footer=True, left=False, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 227,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 739,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 739,
      "hex": "0x02E3",
      "slug": "legacy-e3-mobile",
      "title": "Mobile stack for legacy 0xE3",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE3. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 227,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 227
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 228,
      "hex": "0x00E4",
      "slug": "legacy-e4",
      "title": "Legacy L+M3x4 (0xE4)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE4: header=False, footer=False, left=True, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 228,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 740,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 740,
      "hex": "0x02E4",
      "slug": "legacy-e4-mobile",
      "title": "Mobile stack for legacy 0xE4",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE4. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 228,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 228
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 229,
      "hex": "0x00E5",
      "slug": "legacy-e5",
      "title": "Legacy H+L+M3x4 (0xE5)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE5: header=True, footer=False, left=True, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 229,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 741,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 741,
      "hex": "0x02E5",
      "slug": "legacy-e5-mobile",
      "title": "Mobile stack for legacy 0xE5",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE5. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 229,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 229
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 230,
      "hex": "0x00E6",
      "slug": "legacy-e6",
      "title": "Legacy L+M3x4+F (0xE6)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE6: header=False, footer=True, left=True, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 230,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 742,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 742,
      "hex": "0x02E6",
      "slug": "legacy-e6-mobile",
      "title": "Mobile stack for legacy 0xE6",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE6. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 230,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 230
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 231,
      "hex": "0x00E7",
      "slug": "legacy-e7",
      "title": "Legacy H+L+M3x4+F (0xE7)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE7: header=True, footer=True, left=True, right=False, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 231,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 743,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 743,
      "hex": "0x02E7",
      "slug": "legacy-e7-mobile",
      "title": "Mobile stack for legacy 0xE7",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE7. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 231,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 231
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 232,
      "hex": "0x00E8",
      "slug": "legacy-e8",
      "title": "Legacy M3x4+R (0xE8)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE8: header=False, footer=False, left=False, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m3x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 232,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 744,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 744,
      "hex": "0x02E8",
      "slug": "legacy-e8-mobile",
      "title": "Mobile stack for legacy 0xE8",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE8. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 232,
      "pane_count": 13,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 232
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 233,
      "hex": "0x00E9",
      "slug": "legacy-e9",
      "title": "Legacy H+M3x4+R (0xE9)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xE9: header=True, footer=False, left=False, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 233,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 745,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 745,
      "hex": "0x02E9",
      "slug": "legacy-e9-mobile",
      "title": "Mobile stack for legacy 0xE9",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xE9. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 233,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 233
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 234,
      "hex": "0x00EA",
      "slug": "legacy-ea",
      "title": "Legacy M3x4+R+F (0xEA)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xEA: header=False, footer=True, left=False, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m3x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 234,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 746,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 746,
      "hex": "0x02EA",
      "slug": "legacy-ea-mobile",
      "title": "Mobile stack for legacy 0xEA",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xEA. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 234,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "right",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 13,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 234
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 235,
      "hex": "0x00EB",
      "slug": "legacy-eb",
      "title": "Legacy H+M3x4+R+F (0xEB)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xEB: header=True, footer=True, left=False, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m3x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 235,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 747,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 747,
      "hex": "0x02EB",
      "slug": "legacy-eb-mobile",
      "title": "Mobile stack for legacy 0xEB",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xEB. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 235,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 235
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 236,
      "hex": "0x00EC",
      "slug": "legacy-ec",
      "title": "Legacy L+M3x4+R (0xEC)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xEC: header=False, footer=False, left=True, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 236,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 748,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 748,
      "hex": "0x02EC",
      "slug": "legacy-ec-mobile",
      "title": "Mobile stack for legacy 0xEC",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xEC. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 236,
      "pane_count": 14,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 236
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 237,
      "hex": "0x00ED",
      "slug": "legacy-ed",
      "title": "Legacy H+L+M3x4+R (0xED)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xED: header=True, footer=False, left=True, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 237,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 749,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 749,
      "hex": "0x02ED",
      "slug": "legacy-ed-mobile",
      "title": "Mobile stack for legacy 0xED",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xED. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 237,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 237
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 238,
      "hex": "0x00EE",
      "slug": "legacy-ee",
      "title": "Legacy L+M3x4+R+F (0xEE)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xEE: header=False, footer=True, left=True, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m3x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 238,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 750,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 750,
      "hex": "0x02EE",
      "slug": "legacy-ee-mobile",
      "title": "Mobile stack for legacy 0xEE",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xEE. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 238,
      "pane_count": 15,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "left",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 13,
          "role": "right",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 14,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 238
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 239,
      "hex": "0x00EF",
      "slug": "legacy-ef",
      "title": "Legacy H+L+M3x4+R+F (0xEF)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xEF: header=True, footer=True, left=True, right=True, main=3\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m3x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 239,
      "pane_count": 16,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 15,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 751,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|MMM|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 751,
      "hex": "0x02EF",
      "slug": "legacy-ef-mobile",
      "title": "Mobile stack for legacy 0xEF",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xEF. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 239,
      "pane_count": 16,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "left",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 14,
          "role": "right",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 15,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 239
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 240,
      "hex": "0x00F0",
      "slug": "legacy-f0",
      "title": "Legacy M4x4 (0xF0)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF0: header=False, footer=False, left=False, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m4x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 240,
      "pane_count": 16,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 752,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 752,
      "hex": "0x02F0",
      "slug": "legacy-f0-mobile",
      "title": "Mobile stack for legacy 0xF0",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF0. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 240,
      "pane_count": 16,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 240
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 241,
      "hex": "0x00F1",
      "slug": "legacy-f1",
      "title": "Legacy H+M4x4 (0xF1)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF1: header=True, footer=False, left=False, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 241,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
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          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
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            0
          ],
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
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          "default_width_pct": 25,
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            0,
            0
          ],
          "default_padding_pct": [
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            2,
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            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
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        },
        {
          "index": 7,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
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          "default_margin_pct": [
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            0,
            0
          ],
          "default_padding_pct": [
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            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
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            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
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          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
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            0
          ],
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            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
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            "table"
          ]
        },
        {
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          "role": "main",
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          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
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          ],
          "default_padding_pct": [
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
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          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
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            0,
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            0
          ],
          "default_padding_pct": [
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            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
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            0,
            0,
            0
          ],
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            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
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          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 753,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 753,
      "hex": "0x02F1",
      "slug": "legacy-f1-mobile",
      "title": "Mobile stack for legacy 0xF1",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF1. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 241,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
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            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
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            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
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            0,
            0,
            0
          ],
          "default_padding_pct": [
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            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
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            2,
            2,
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 241
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 242,
      "hex": "0x00F2",
      "slug": "legacy-f2",
      "title": "Legacy M4x4+F (0xF2)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF2: header=False, footer=True, left=False, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m4x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 242,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 754,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 754,
      "hex": "0x02F2",
      "slug": "legacy-f2-mobile",
      "title": "Mobile stack for legacy 0xF2",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF2. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 242,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 242
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 243,
      "hex": "0x00F3",
      "slug": "legacy-f3",
      "title": "Legacy H+M4x4+F (0xF3)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF3: header=True, footer=True, left=False, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 243,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 755,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 755,
      "hex": "0x02F3",
      "slug": "legacy-f3-mobile",
      "title": "Mobile stack for legacy 0xF3",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF3. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 243,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 243
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 244,
      "hex": "0x00F4",
      "slug": "legacy-f4",
      "title": "Legacy L+M4x4 (0xF4)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF4: header=False, footer=False, left=True, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 244,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 756,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 756,
      "hex": "0x02F4",
      "slug": "legacy-f4-mobile",
      "title": "Mobile stack for legacy 0xF4",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF4. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 244,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "left",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 244
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 245,
      "hex": "0x00F5",
      "slug": "legacy-f5",
      "title": "Legacy H+L+M4x4 (0xF5)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF5: header=True, footer=False, left=True, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x4"
      ],
      "viewport": "desktop",
      "legacy_byte": 245,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 757,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 757,
      "hex": "0x02F5",
      "slug": "legacy-f5-mobile",
      "title": "Mobile stack for legacy 0xF5",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF5. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 245,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "left",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 245
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 246,
      "hex": "0x00F6",
      "slug": "legacy-f6",
      "title": "Legacy L+M4x4+F (0xF6)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF6: header=False, footer=True, left=True, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 246,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 758,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 758,
      "hex": "0x02F6",
      "slug": "legacy-f6-mobile",
      "title": "Mobile stack for legacy 0xF6",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF6. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 246,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "left",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 17,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 246
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 247,
      "hex": "0x00F7",
      "slug": "legacy-f7",
      "title": "Legacy H+L+M4x4+F (0xF7)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF7: header=True, footer=True, left=True, right=False, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x4+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 247,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 18,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 759,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 759,
      "hex": "0x02F7",
      "slug": "legacy-f7-mobile",
      "title": "Mobile stack for legacy 0xF7",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF7. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 247,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "left",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 18,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 18,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 247
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 248,
      "hex": "0x00F8",
      "slug": "legacy-f8",
      "title": "Legacy M4x4+R (0xF8)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF8: header=False, footer=False, left=False, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m4x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 248,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 760,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 760,
      "hex": "0x02F8",
      "slug": "legacy-f8-mobile",
      "title": "Mobile stack for legacy 0xF8",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF8. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 248,
      "pane_count": 17,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "right",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 248
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 249,
      "hex": "0x00F9",
      "slug": "legacy-f9",
      "title": "Legacy H+M4x4+R (0xF9)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xF9: header=True, footer=False, left=False, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 249,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 761,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 761,
      "hex": "0x02F9",
      "slug": "legacy-f9-mobile",
      "title": "Mobile stack for legacy 0xF9",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xF9. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 249,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 249
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 250,
      "hex": "0x00FA",
      "slug": "legacy-fa",
      "title": "Legacy M4x4+R+F (0xFA)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xFA: header=False, footer=True, left=False, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "m4x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 250,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 17,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 762,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 762,
      "hex": "0x02FA",
      "slug": "legacy-fa-mobile",
      "title": "Mobile stack for legacy 0xFA",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xFA. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 250,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "right",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 17,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 250
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 251,
      "hex": "0x00FB",
      "slug": "legacy-fb",
      "title": "Legacy H+M4x4+R+F (0xFB)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xFB: header=True, footer=True, left=False, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+m4x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 251,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 18,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 763,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 763,
      "hex": "0x02FB",
      "slug": "legacy-fb-mobile",
      "title": "Mobile stack for legacy 0xFB",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xFB. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 251,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 18,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 18,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 251
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 252,
      "hex": "0x00FC",
      "slug": "legacy-fc",
      "title": "Legacy L+M4x4+R (0xFC)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xFC: header=False, footer=False, left=True, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 252,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 764,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 764,
      "hex": "0x02FC",
      "slug": "legacy-fc-mobile",
      "title": "Mobile stack for legacy 0xFC",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xFC. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 252,
      "pane_count": 18,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "left",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 252
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 253,
      "hex": "0x00FD",
      "slug": "legacy-fd",
      "title": "Legacy H+L+M4x4+R (0xFD)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xFD: header=True, footer=False, left=True, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x4+r"
      ],
      "viewport": "desktop",
      "legacy_byte": 253,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 3,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 1,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 18,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 765,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 765,
      "hex": "0x02FD",
      "slug": "legacy-fd-mobile",
      "title": "Mobile stack for legacy 0xFD",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xFD. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 253,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "left",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 18,
          "role": "right",
          "grid_col": 0,
          "grid_row": 18,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 253
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 254,
      "hex": "0x00FE",
      "slug": "legacy-fe",
      "title": "Legacy L+M4x4+R+F (0xFE)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xFE: header=False, footer=True, left=True, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "l+m4x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 254,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
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          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
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          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 2,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 3,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 1,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 2,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 3,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 18,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 766,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 766,
      "hex": "0x02FE",
      "slug": "legacy-fe-mobile",
      "title": "Mobile stack for legacy 0xFE",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xFE. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 254,
      "pane_count": 19,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
          ]
        },
        {
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          "role": "main",
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          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          "default_margin_pct": [
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          "default_padding_pct": [
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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        },
        {
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          "full_height_bottom": false,
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          "default_height_pct": null,
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          "default_padding_pct": [
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        },
        {
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          "full_height_top": false,
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          ],
          "default_padding_pct": [
            2,
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            2
          ],
          "nav_host": false,
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            "text",
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        },
        {
          "index": 4,
          "role": "main",
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          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
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          ],
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          ]
        },
        {
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            2
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          "nav_host": false,
          "recommended_content": [
            "text",
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        },
        {
          "index": 6,
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          "full_height_top": false,
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          "nav_host": false,
          "recommended_content": [
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        },
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          "index": 7,
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          "full_height_top": false,
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        },
        {
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        {
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          ],
          "nav_host": false,
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        },
        {
          "index": 10,
          "role": "main",
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          "full_height_top": false,
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          "default_width_pct": 100,
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          ],
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          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
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          "grid_row": 11,
          "full_height_top": false,
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          "default_width_pct": 100,
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          ],
          "nav_host": false,
          "recommended_content": [
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          ]
        },
        {
          "index": 12,
          "role": "main",
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          "full_height_top": false,
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          "default_width_pct": 100,
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          ],
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
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          "grid_row": 13,
          "full_height_top": false,
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          "default_width_pct": 100,
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          ],
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          ],
          "nav_host": false,
          "recommended_content": [
            "text",
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          ]
        },
        {
          "index": 14,
          "role": "main",
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          "default_width_pct": 100,
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          ],
          "default_padding_pct": [
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            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "left",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
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            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 17,
          "role": "right",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 18,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 18,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 254
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 255,
      "hex": "0x00FF",
      "slug": "legacy-ff",
      "title": "Legacy H+L+M4x4+R+F (0xFF)",
      "category": "legacy",
      "description": "Compatibility layout from 1-byte bitfield 0xFF: header=True, footer=True, left=True, right=True, main=4\u00d74.",
      "tags": [
        "legacy",
        "compat",
        "h+l+m4x4+r+f"
      ],
      "viewport": "desktop",
      "legacy_byte": 255,
      "pane_count": 20,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
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          "default_height_pct": 10,
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            0,
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          ],
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            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
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            "text",
            "image"
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        },
        {
          "index": 1,
          "role": "left",
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          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
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            0
          ],
          "default_padding_pct": [
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            2,
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            2
          ],
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          "recommended_content": [
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          ]
        },
        {
          "index": 2,
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          "full_height_bottom": false,
          "default_width_pct": 25,
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          "default_margin_pct": [
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          ],
          "default_padding_pct": [
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          ],
          "nav_host": false,
          "recommended_content": [
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        },
        {
          "index": 3,
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          ],
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        },
        {
          "index": 4,
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          ]
        },
        {
          "index": 5,
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          ]
        },
        {
          "index": 6,
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        {
          "index": 12,
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        },
        {
          "index": 13,
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          "nav_host": false,
          "recommended_content": [
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        },
        {
          "index": 14,
          "role": "main",
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        },
        {
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        },
        {
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        {
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            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 18,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 19,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 767,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email",
        "qweb",
        "migration"
      ],
      "ascii_preview": "+--HEADER (nav)--+\n|L|M\u00d74|R|\n+--FOOTER--------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 767,
      "hex": "0x02FF",
      "slug": "legacy-ff-mobile",
      "title": "Mobile stack for legacy 0xFF",
      "category": "legacy-mobile",
      "description": "Single-column collapse of legacy layout 0xFF. Order: header, main cells, left, right, footer.",
      "tags": [
        "legacy",
        "mobile",
        "stack"
      ],
      "viewport": "mobile",
      "legacy_byte": 255,
      "pane_count": 20,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 7,
          "role": "main",
          "grid_col": 0,
          "grid_row": 7,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 8,
          "role": "main",
          "grid_col": 0,
          "grid_row": 8,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 9,
          "role": "main",
          "grid_col": 0,
          "grid_row": 9,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 10,
          "role": "main",
          "grid_col": 0,
          "grid_row": 10,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 11,
          "role": "main",
          "grid_col": 0,
          "grid_row": 11,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 12,
          "role": "main",
          "grid_col": 0,
          "grid_row": 12,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 13,
          "role": "main",
          "grid_col": 0,
          "grid_row": 13,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 14,
          "role": "main",
          "grid_col": 0,
          "grid_row": 14,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 15,
          "role": "main",
          "grid_col": 0,
          "grid_row": 15,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 16,
          "role": "main",
          "grid_col": 0,
          "grid_row": 16,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 17,
          "role": "left",
          "grid_col": 0,
          "grid_row": 17,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 18,
          "role": "right",
          "grid_col": 0,
          "grid_row": 18,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 19,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 19,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            1,
            2,
            1,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 255
      },
      "use_cases": [
        "mobile",
        "narrow"
      ],
      "ascii_preview": "[H?]\n[M\u2026]\n[L?]\n[R?]\n[F?]",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 256,
      "hex": "0x0100",
      "slug": "email-simple",
      "title": "Simple single column",
      "category": "email",
      "description": "Single main body \u2014 classic email or article. No chrome.",
      "tags": [
        "email",
        "qmail",
        "article"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 768,
        "desktop_layout_id": null
      },
      "use_cases": [
        "qmail plain",
        "article",
        "sms-class body"
      ],
      "ascii_preview": "+----------+\n|   MAIN   |\n+----------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 768,
      "hex": "0x0300",
      "slug": "email-simple-mobile",
      "title": "Simple single column (mobile)",
      "category": "email-mobile",
      "description": "Mobile stack for email-simple. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "email",
        "qmail",
        "article",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 256
      },
      "use_cases": [
        "qmail plain",
        "article",
        "sms-class body",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 257,
      "hex": "0x0101",
      "slug": "email-header-footer",
      "title": "Email with header and footer",
      "category": "email",
      "description": "Header band (logo/subject chrome), main body, footer signature band.",
      "tags": [
        "email",
        "newsletter"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "image",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 769,
        "desktop_layout_id": null
      },
      "use_cases": [
        "qmail branded",
        "newsletter"
      ],
      "ascii_preview": "+--HEADER--+\n|   MAIN   |\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 769,
      "hex": "0x0301",
      "slug": "email-header-footer-mobile",
      "title": "Email with header and footer (mobile)",
      "category": "email-mobile",
      "description": "Mobile stack for email-header-footer. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "email",
        "newsletter",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "image",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 257
      },
      "use_cases": [
        "qmail branded",
        "newsletter",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 258,
      "hex": "0x0102",
      "slug": "email-header-main",
      "title": "Header + main",
      "category": "email",
      "description": "Top chrome with body; no footer pane.",
      "tags": [
        "email"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 770,
        "desktop_layout_id": null
      },
      "use_cases": [
        "qmail",
        "notice"
      ],
      "ascii_preview": "+--HEADER--+\n|   MAIN   |",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 770,
      "hex": "0x0302",
      "slug": "email-header-main-mobile",
      "title": "Header + main (mobile)",
      "category": "email-mobile",
      "description": "Mobile stack for email-header-main. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "email",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 258
      },
      "use_cases": [
        "qmail",
        "notice",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 259,
      "hex": "0x0103",
      "slug": "blog-right-sidebar",
      "title": "Blog / docs with right sidebar",
      "category": "blog",
      "description": "Header nav, main article, right rail (TOC/related), footer.",
      "tags": [
        "blog",
        "docs",
        "cms"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 70,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 30,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 771,
        "desktop_layout_id": null
      },
      "use_cases": [
        "blog post",
        "documentation",
        "news article"
      ],
      "ascii_preview": "+----HEADER-----+\n| MAIN  | RIGHT |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 771,
      "hex": "0x0303",
      "slug": "blog-right-sidebar-mobile",
      "title": "Blog / docs with right sidebar (mobile)",
      "category": "blog-mobile",
      "description": "Mobile stack for blog-right-sidebar. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "blog",
        "docs",
        "cms",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 259
      },
      "use_cases": [
        "blog post",
        "documentation",
        "news article",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 260,
      "hex": "0x0104",
      "slug": "blog-left-sidebar",
      "title": "Blog / docs with left sidebar",
      "category": "blog",
      "description": "Left nav/TOC rail, main content, header and footer.",
      "tags": [
        "blog",
        "docs",
        "wiki"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 75,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 772,
        "desktop_layout_id": null
      },
      "use_cases": [
        "docs site",
        "knowledge base"
      ],
      "ascii_preview": "+----HEADER-----+\n| L |   MAIN    |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 772,
      "hex": "0x0304",
      "slug": "blog-left-sidebar-mobile",
      "title": "Blog / docs with left sidebar (mobile)",
      "category": "blog-mobile",
      "description": "Mobile stack for blog-left-sidebar. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "blog",
        "docs",
        "wiki",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 260
      },
      "use_cases": [
        "docs site",
        "knowledge base",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 261,
      "hex": "0x0105",
      "slug": "app-triple-column",
      "title": "Header + left + main + right + footer",
      "category": "app",
      "description": "Classic app shell: top bar, left nav, content, right context, footer.",
      "tags": [
        "app",
        "admin",
        "dashboard"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 18,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 64,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 18,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 773,
        "desktop_layout_id": null
      },
      "use_cases": [
        "admin console",
        "mail client",
        "IDE-like page"
      ],
      "ascii_preview": "+------HEADER-------+\n| L |  MAIN  |  R  |\n+------FOOTER-------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 773,
      "hex": "0x0305",
      "slug": "app-triple-column-mobile",
      "title": "Header + left + main + right + footer (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for app-triple-column. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "admin",
        "dashboard",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 261
      },
      "use_cases": [
        "admin console",
        "mail client",
        "IDE-like page",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 262,
      "hex": "0x0106",
      "slug": "dashboard-left-rail",
      "title": "Dashboard with full-height left rail",
      "category": "dashboard",
      "description": "Left nav spans full height (beside header/footer). Main content + top header strip for breadcrumbs.",
      "tags": [
        "dashboard",
        "admin",
        "saas"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ],
          "notes": "Sits to the right of full-height left in many renderers; index still header-first for reading."
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": true,
          "full_height_bottom": true,
          "default_width_pct": 18,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 82,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 774,
        "desktop_layout_id": null
      },
      "use_cases": [
        "SaaS app",
        "analytics",
        "settings"
      ],
      "ascii_preview": "L | HEADER\nL | MAIN\nL | FOOTER",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 774,
      "hex": "0x0306",
      "slug": "dashboard-left-rail-mobile",
      "title": "Dashboard with full-height left rail (mobile)",
      "category": "dashboard-mobile",
      "description": "Mobile stack for dashboard-left-rail. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "dashboard",
        "admin",
        "saas",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "nav"
          ],
          "notes": "Sits to the right of full-height left in many renderers; index still header-first for reading."
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 262
      },
      "use_cases": [
        "SaaS app",
        "analytics",
        "settings",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 263,
      "hex": "0x0107",
      "slug": "dashboard-left-rail-nofooter",
      "title": "Full-height left rail, no footer",
      "category": "dashboard",
      "description": "App chrome without footer pane.",
      "tags": [
        "dashboard",
        "app"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": true,
          "full_height_bottom": true,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 775,
        "desktop_layout_id": null
      },
      "use_cases": [
        "SPA shell",
        "admin"
      ],
      "ascii_preview": "L | HEADER\nL | MAIN",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 775,
      "hex": "0x0307",
      "slug": "dashboard-left-rail-nofooter-mobile",
      "title": "Full-height left rail, no footer (mobile)",
      "category": "dashboard-mobile",
      "description": "Mobile stack for dashboard-left-rail-nofooter. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "dashboard",
        "app",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 263
      },
      "use_cases": [
        "SPA shell",
        "admin",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 264,
      "hex": "0x0108",
      "slug": "landing-hero",
      "title": "Landing page hero + main + footer",
      "category": "landing",
      "description": "Marketing landing: wide header/hero, single main, footer with links.",
      "tags": [
        "landing",
        "marketing"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 28,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            3,
            4,
            3,
            4
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 776,
        "desktop_layout_id": null
      },
      "use_cases": [
        "product page",
        "campaign",
        "signup"
      ],
      "ascii_preview": "+--HERO/HEADER--+\n|     MAIN      |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 776,
      "hex": "0x0308",
      "slug": "landing-hero-mobile",
      "title": "Landing page hero + main + footer (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for landing-hero. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "landing",
        "marketing",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 28,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            3,
            4,
            3,
            4
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 264
      },
      "use_cases": [
        "product page",
        "campaign",
        "signup",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 265,
      "hex": "0x0109",
      "slug": "split-screen-2",
      "title": "Split screen two columns",
      "category": "landing",
      "description": "Two equal main columns (1\u00d72 grid), optional header for logo/nav.",
      "tags": [
        "landing",
        "split",
        "auth"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 777,
        "desktop_layout_id": null
      },
      "use_cases": [
        "login/signup split",
        "feature compare",
        "before/after"
      ],
      "ascii_preview": "+--HEADER--+\n| M0 | M1  |",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 777,
      "hex": "0x0309",
      "slug": "split-screen-2-mobile",
      "title": "Split screen two columns (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for split-screen-2. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "landing",
        "split",
        "auth",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 265
      },
      "use_cases": [
        "login/signup split",
        "feature compare",
        "before/after",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 266,
      "hex": "0x010A",
      "slug": "split-screen-2-footer",
      "title": "Split screen + footer",
      "category": "landing",
      "description": "Two-column main with footer legal/links.",
      "tags": [
        "landing",
        "split"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 778,
        "desktop_layout_id": null
      },
      "use_cases": [
        "marketing",
        "onboarding"
      ],
      "ascii_preview": "+--HEADER--+\n| M0 | M1  |\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 778,
      "hex": "0x030A",
      "slug": "split-screen-2-footer-mobile",
      "title": "Split screen + footer (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for split-screen-2-footer. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "landing",
        "split",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 266
      },
      "use_cases": [
        "marketing",
        "onboarding",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 267,
      "hex": "0x010B",
      "slug": "grid-3-col",
      "title": "Three-column content grid",
      "category": "grid",
      "description": "Header, three main columns, footer. Card/feature rows.",
      "tags": [
        "grid",
        "features",
        "pricing"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 34,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 33,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 779,
        "desktop_layout_id": null
      },
      "use_cases": [
        "pricing tiers",
        "feature cards",
        "team"
      ],
      "ascii_preview": "+----HEADER-----+\n|M0 | M1 | M2 |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 779,
      "hex": "0x030B",
      "slug": "grid-3-col-mobile",
      "title": "Three-column content grid (mobile)",
      "category": "grid-mobile",
      "description": "Mobile stack for grid-3-col. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "grid",
        "features",
        "pricing",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 267
      },
      "use_cases": [
        "pricing tiers",
        "feature cards",
        "team",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 268,
      "hex": "0x010C",
      "slug": "grid-2x2",
      "title": "2\u00d72 main grid",
      "category": "grid",
      "description": "Header + 2\u00d72 main cells + footer. Dashboard tiles or gallery.",
      "tags": [
        "grid",
        "dashboard",
        "gallery"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 780,
        "desktop_layout_id": null
      },
      "use_cases": [
        "KPI quadrants",
        "gallery",
        "widgets"
      ],
      "ascii_preview": "+--HEADER--+\n| M0 | M1 |\n| M2 | M3 |\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 780,
      "hex": "0x030C",
      "slug": "grid-2x2-mobile",
      "title": "2\u00d72 main grid (mobile)",
      "category": "grid-mobile",
      "description": "Mobile stack for grid-2x2. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "grid",
        "dashboard",
        "gallery",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 268
      },
      "use_cases": [
        "KPI quadrants",
        "gallery",
        "widgets",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 269,
      "hex": "0x010D",
      "slug": "grid-2x2-bare",
      "title": "2\u00d72 grid only",
      "category": "grid",
      "description": "Four main cells, no header/footer \u2014 embed/widget board.",
      "tags": [
        "grid",
        "embed"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 781,
        "desktop_layout_id": null
      },
      "use_cases": [
        "tile board",
        "comparison"
      ],
      "ascii_preview": "| M0 | M1 |\n| M2 | M3 |",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 781,
      "hex": "0x030D",
      "slug": "grid-2x2-bare-mobile",
      "title": "2\u00d72 grid only (mobile)",
      "category": "grid-mobile",
      "description": "Mobile stack for grid-2x2-bare. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "grid",
        "embed",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 269
      },
      "use_cases": [
        "tile board",
        "comparison",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 270,
      "hex": "0x010E",
      "slug": "grid-3x2",
      "title": "3\u00d72 main grid with header",
      "category": "grid",
      "description": "Six main cells in 3 cols \u00d7 2 rows under a header.",
      "tags": [
        "grid",
        "gallery",
        "shop"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 1,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 2,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 782,
        "desktop_layout_id": null
      },
      "use_cases": [
        "product grid",
        "photo gallery"
      ],
      "ascii_preview": "+----HEADER-----+\n|0|1|2|\n|3|4|5|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 782,
      "hex": "0x030E",
      "slug": "grid-3x2-mobile",
      "title": "3\u00d72 main grid with header (mobile)",
      "category": "grid-mobile",
      "description": "Mobile stack for grid-3x2. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "grid",
        "gallery",
        "shop",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 7,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "main",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 6,
          "role": "main",
          "grid_col": 0,
          "grid_row": 6,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 270
      },
      "use_cases": [
        "product grid",
        "photo gallery",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 271,
      "hex": "0x010F",
      "slug": "grid-4-col",
      "title": "Four-column strip",
      "category": "grid",
      "description": "Header and four equal main columns.",
      "tags": [
        "grid",
        "portfolio"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 783,
        "desktop_layout_id": null
      },
      "use_cases": [
        "services",
        "portfolio strip"
      ],
      "ascii_preview": "+------HEADER-------+\n|0|1|2|3|\n+------FOOTER-------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 783,
      "hex": "0x030F",
      "slug": "grid-4-col-mobile",
      "title": "Four-column strip (mobile)",
      "category": "grid-mobile",
      "description": "Mobile stack for grid-4-col. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "grid",
        "portfolio",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 271
      },
      "use_cases": [
        "services",
        "portfolio strip",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 272,
      "hex": "0x0110",
      "slug": "shop-filters-left",
      "title": "Shop with left filters",
      "category": "ecommerce",
      "description": "Header (cart/nav), left filters, main product area, footer.",
      "tags": [
        "ecommerce",
        "shop",
        "catalog"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 22,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ],
          "notes": "filters"
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 78,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 784,
        "desktop_layout_id": null
      },
      "use_cases": [
        "product list",
        "marketplace"
      ],
      "ascii_preview": "+----HEADER-----+\n|FIL| PRODUCTS  |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 784,
      "hex": "0x0310",
      "slug": "shop-filters-left-mobile",
      "title": "Shop with left filters (mobile)",
      "category": "ecommerce-mobile",
      "description": "Mobile stack for shop-filters-left. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "ecommerce",
        "shop",
        "catalog",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ],
          "notes": "filters"
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 272
      },
      "use_cases": [
        "product list",
        "marketplace",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 273,
      "hex": "0x0111",
      "slug": "shop-product-detail",
      "title": "Product detail split",
      "category": "ecommerce",
      "description": "Header, left media, right details, footer.",
      "tags": [
        "ecommerce",
        "product"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 785,
        "desktop_layout_id": null
      },
      "use_cases": [
        "PDP",
        "item view"
      ],
      "ascii_preview": "+--HEADER--+\n|IMG | INFO|\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 785,
      "hex": "0x0311",
      "slug": "shop-product-detail-mobile",
      "title": "Product detail split (mobile)",
      "category": "ecommerce-mobile",
      "description": "Mobile stack for shop-product-detail. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "ecommerce",
        "product",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 273
      },
      "use_cases": [
        "PDP",
        "item view",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 274,
      "hex": "0x0112",
      "slug": "portfolio-3col",
      "title": "Portfolio three columns",
      "category": "portfolio",
      "description": "Minimal header + 3 image columns.",
      "tags": [
        "portfolio",
        "gallery"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 786,
        "desktop_layout_id": null
      },
      "use_cases": [
        "creative portfolio",
        "gallery"
      ],
      "ascii_preview": "+--HEADER--+\n| A | B | C |",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 786,
      "hex": "0x0312",
      "slug": "portfolio-3col-mobile",
      "title": "Portfolio three columns (mobile)",
      "category": "portfolio-mobile",
      "description": "Mobile stack for portfolio-3col. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "portfolio",
        "gallery",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 274
      },
      "use_cases": [
        "creative portfolio",
        "gallery",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 275,
      "hex": "0x0113",
      "slug": "docs-full-left-nav",
      "title": "Documentation full-height nav",
      "category": "docs",
      "description": "Full-height left documentation nav, header, scrolling main.",
      "tags": [
        "docs",
        "wiki",
        "api"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": true,
          "full_height_bottom": true,
          "default_width_pct": 24,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 787,
        "desktop_layout_id": null
      },
      "use_cases": [
        "API docs",
        "manual",
        "wiki"
      ],
      "ascii_preview": "L | HEADER\nL | DOCS MAIN",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 787,
      "hex": "0x0313",
      "slug": "docs-full-left-nav-mobile",
      "title": "Documentation full-height nav (mobile)",
      "category": "docs-mobile",
      "description": "Mobile stack for docs-full-left-nav. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "docs",
        "wiki",
        "api",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 275
      },
      "use_cases": [
        "API docs",
        "manual",
        "wiki",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 276,
      "hex": "0x0114",
      "slug": "docs-left-right-toc",
      "title": "Docs nav + main + on-this-page",
      "category": "docs",
      "description": "Left site nav, main article, right on-page TOC.",
      "tags": [
        "docs",
        "wiki"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 55,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ],
          "notes": "on-this-page"
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 788,
        "desktop_layout_id": null
      },
      "use_cases": [
        "long-form docs",
        "handbook"
      ],
      "ascii_preview": "+------HEADER-------+\n| L | MAIN | TOC  |\n+------FOOTER-------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 788,
      "hex": "0x0314",
      "slug": "docs-left-right-toc-mobile",
      "title": "Docs nav + main + on-this-page (mobile)",
      "category": "docs-mobile",
      "description": "Mobile stack for docs-left-right-toc. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "docs",
        "wiki",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ],
          "notes": "on-this-page"
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 276
      },
      "use_cases": [
        "long-form docs",
        "handbook",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 277,
      "hex": "0x0115",
      "slug": "magazine-main-rail",
      "title": "Magazine main + right rail",
      "category": "news",
      "description": "Header, two-row main feature area as 2-col top + full bottom via 2x2 partial \u2014 simplified as header, 2-col main, right, footer.",
      "tags": [
        "news",
        "magazine"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 45,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 30,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 789,
        "desktop_layout_id": null
      },
      "use_cases": [
        "news home",
        "magazine"
      ],
      "ascii_preview": "+----HEADER-----+\n|M0|M1| RIGHT |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 789,
      "hex": "0x0315",
      "slug": "magazine-main-rail-mobile",
      "title": "Magazine main + right rail (mobile)",
      "category": "news-mobile",
      "description": "Mobile stack for magazine-main-rail. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "news",
        "magazine",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "image"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 277
      },
      "use_cases": [
        "news home",
        "magazine",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 278,
      "hex": "0x0116",
      "slug": "qmail-receipt",
      "title": "QMail receipt / notice",
      "category": "email",
      "description": "Compact notice: optional header strip + main. Good for system mail.",
      "tags": [
        "email",
        "system",
        "qmail"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 790,
        "desktop_layout_id": null
      },
      "use_cases": [
        "receipt",
        "alert notice",
        "invoice summary"
      ],
      "ascii_preview": "+-TITLE-+\n| BODY  |",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 790,
      "hex": "0x0316",
      "slug": "qmail-receipt-mobile",
      "title": "QMail receipt / notice (mobile)",
      "category": "email-mobile",
      "description": "Mobile stack for qmail-receipt. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "email",
        "system",
        "qmail",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 278
      },
      "use_cases": [
        "receipt",
        "alert notice",
        "invoice summary",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 279,
      "hex": "0x0117",
      "slug": "qmail-newsletter",
      "title": "Newsletter columns",
      "category": "email",
      "description": "Newsletter: header brand, 2 content columns, footer unsubscribe.",
      "tags": [
        "email",
        "newsletter",
        "qmail"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 15,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "image",
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 791,
        "desktop_layout_id": null
      },
      "use_cases": [
        "email newsletter",
        "digest"
      ],
      "ascii_preview": "+--BRAND--+\n| A  | B  |\n+-UNSUB---+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 791,
      "hex": "0x0317",
      "slug": "qmail-newsletter-mobile",
      "title": "Newsletter columns (mobile)",
      "category": "email-mobile",
      "description": "Mobile stack for qmail-newsletter. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "email",
        "newsletter",
        "qmail",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 15,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "image",
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 279
      },
      "use_cases": [
        "email newsletter",
        "digest",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 280,
      "hex": "0x0118",
      "slug": "modal-center",
      "title": "Main with center modal overlay",
      "category": "overlay",
      "description": "Full-page main (dimmed) + overlay pane for modal/dialog. Overlay indexes last.",
      "tags": [
        "modal",
        "dialog",
        "overlay"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ],
          "notes": "background page"
        },
        {
          "index": 1,
          "role": "overlay",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 50,
          "default_height_pct": 60,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            4,
            4,
            4,
            4
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "image"
          ],
          "notes": "modal; composite layer_id=10"
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 792,
        "desktop_layout_id": null
      },
      "use_cases": [
        "confirm dialog",
        "soft paywall",
        "feature spotlight"
      ],
      "ascii_preview": "[ MAIN background ]\n   +--MODAL--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 792,
      "hex": "0x0318",
      "slug": "modal-center-mobile",
      "title": "Main with center modal overlay (mobile)",
      "category": "overlay-mobile",
      "description": "Mobile stack for modal-center. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "modal",
        "dialog",
        "overlay",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ],
          "notes": "background page"
        },
        {
          "index": 1,
          "role": "overlay",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 60,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            4,
            4,
            4,
            4
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "image"
          ],
          "notes": "modal; composite layer_id=10"
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 280
      },
      "use_cases": [
        "confirm dialog",
        "soft paywall",
        "feature spotlight",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 281,
      "hex": "0x0119",
      "slug": "modal-over-app",
      "title": "App shell with modal overlay",
      "category": "overlay",
      "description": "Header+main shell with modal overlay pane.",
      "tags": [
        "modal",
        "app"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "overlay",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 40,
          "default_height_pct": 50,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ],
          "notes": "layer_id=10 modal"
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 793,
        "desktop_layout_id": null
      },
      "use_cases": [
        "in-app dialog"
      ],
      "ascii_preview": "+HEADER+\n| MAIN | +MODAL+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 793,
      "hex": "0x0319",
      "slug": "modal-over-app-mobile",
      "title": "App shell with modal overlay (mobile)",
      "category": "overlay-mobile",
      "description": "Mobile stack for modal-over-app. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "modal",
        "app",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "overlay",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 50,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ],
          "notes": "layer_id=10 modal"
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 281
      },
      "use_cases": [
        "in-app dialog",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 282,
      "hex": "0x011A",
      "slug": "alert-banner-main",
      "title": "Alert header + main",
      "category": "email",
      "description": "Thin alert/disclaimer header band + body. Use layer disclaimer styles on header.",
      "tags": [
        "email",
        "legal",
        "alert"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ],
          "notes": "alert/disclaimer band"
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 794,
        "desktop_layout_id": null
      },
      "use_cases": [
        "legal notice",
        "outage banner"
      ],
      "ascii_preview": "+-ALERT--+\n|  BODY  |\n+-FOOT---+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 794,
      "hex": "0x031A",
      "slug": "alert-banner-main-mobile",
      "title": "Alert header + main (mobile)",
      "category": "email-mobile",
      "description": "Mobile stack for alert-banner-main. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "email",
        "legal",
        "alert",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text"
          ],
          "notes": "alert/disclaimer band"
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 282
      },
      "use_cases": [
        "legal notice",
        "outage banner",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 283,
      "hex": "0x011B",
      "slug": "pricing-3",
      "title": "Pricing three tiers",
      "category": "landing",
      "description": "Header, three pricing columns, footer CTA strip.",
      "tags": [
        "pricing",
        "landing",
        "saas"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 795,
        "desktop_layout_id": null
      },
      "use_cases": [
        "pricing page",
        "plans"
      ],
      "ascii_preview": "+---HEADER----+\n| $ | $$ | $$$|\n+---FOOTER----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 795,
      "hex": "0x031B",
      "slug": "pricing-3-mobile",
      "title": "Pricing three tiers (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for pricing-3. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "pricing",
        "landing",
        "saas",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 283
      },
      "use_cases": [
        "pricing page",
        "plans",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 284,
      "hex": "0x011C",
      "slug": "contact-split",
      "title": "Contact form split",
      "category": "landing",
      "description": "Left info, right form (two main cols), header nav.",
      "tags": [
        "contact",
        "landing",
        "form"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ],
          "notes": "form fields as lists/tables Phase II"
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 796,
        "desktop_layout_id": null
      },
      "use_cases": [
        "contact page",
        "support request"
      ],
      "ascii_preview": "+--HEADER--+\n|INFO| FORM|\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 796,
      "hex": "0x031C",
      "slug": "contact-split-mobile",
      "title": "Contact form split (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for contact-split. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "contact",
        "landing",
        "form",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ],
          "notes": "form fields as lists/tables Phase II"
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 284
      },
      "use_cases": [
        "contact page",
        "support request",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 285,
      "hex": "0x011D",
      "slug": "inbox-list-detail",
      "title": "Inbox list + detail",
      "category": "app",
      "description": "Header, left list pane, main detail pane.",
      "tags": [
        "app",
        "mail",
        "messages"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 32,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ],
          "notes": "message list"
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 68,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 797,
        "desktop_layout_id": null
      },
      "use_cases": [
        "mail reader",
        "ticket detail",
        "chat list"
      ],
      "ascii_preview": "+--HEADER--+\n|LIST| DETAIL|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 797,
      "hex": "0x031D",
      "slug": "inbox-list-detail-mobile",
      "title": "Inbox list + detail (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for inbox-list-detail. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "mail",
        "messages",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ],
          "notes": "message list"
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 285
      },
      "use_cases": [
        "mail reader",
        "ticket detail",
        "chat list",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 286,
      "hex": "0x011E",
      "slug": "timeline-single",
      "title": "Timeline / feed single column",
      "category": "social",
      "description": "Header + single scrolling main feed.",
      "tags": [
        "social",
        "feed",
        "blog"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ],
          "notes": "optional bottom tabs via nav in footer"
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "bottom_tabs",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 798,
        "desktop_layout_id": null
      },
      "use_cases": [
        "activity feed",
        "microblog"
      ],
      "ascii_preview": "+-TOP NAV-+\n|  FEED   |\n+-TABS?---+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 798,
      "hex": "0x031E",
      "slug": "timeline-single-mobile",
      "title": "Timeline / feed single column (mobile)",
      "category": "social-mobile",
      "description": "Mobile stack for timeline-single. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "social",
        "feed",
        "blog",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ],
          "notes": "optional bottom tabs via nav in footer"
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 286
      },
      "use_cases": [
        "activity feed",
        "microblog",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 287,
      "hex": "0x011F",
      "slug": "settings-nav-main",
      "title": "Settings: nav + panel",
      "category": "app",
      "description": "Left settings sections, main settings form.",
      "tags": [
        "settings",
        "app"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 28,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 799,
        "desktop_layout_id": null
      },
      "use_cases": [
        "account settings",
        "preferences"
      ],
      "ascii_preview": "+-HEADER-+\n|NAV| FORM|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 799,
      "hex": "0x031F",
      "slug": "settings-nav-main-mobile",
      "title": "Settings: nav + panel (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for settings-nav-main. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "settings",
        "app",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 287
      },
      "use_cases": [
        "account settings",
        "preferences",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 288,
      "hex": "0x0120",
      "slug": "invoice-document",
      "title": "Invoice / formal document",
      "category": "document",
      "description": "Header letterhead, main tables/text, footer totals/legal.",
      "tags": [
        "document",
        "invoice",
        "email"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 15,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 800,
        "desktop_layout_id": null
      },
      "use_cases": [
        "invoice",
        "contract summary",
        "statement"
      ],
      "ascii_preview": "+-LETTERHEAD-+\n|  INVOICE   |\n+-TOTALS/LEGAL+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 800,
      "hex": "0x0320",
      "slug": "invoice-document-mobile",
      "title": "Invoice / formal document (mobile)",
      "category": "document-mobile",
      "description": "Mobile stack for invoice-document. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "document",
        "invoice",
        "email",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 15,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 288
      },
      "use_cases": [
        "invoice",
        "contract summary",
        "statement",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 289,
      "hex": "0x0121",
      "slug": "compare-two",
      "title": "Two-product comparison",
      "category": "landing",
      "description": "Header, two equal columns for A vs B, footer.",
      "tags": [
        "compare",
        "landing"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 801,
        "desktop_layout_id": null
      },
      "use_cases": [
        "A/B features",
        "plan compare"
      ],
      "ascii_preview": "+--HEADER--+\n|  A  |  B  |\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 801,
      "hex": "0x0321",
      "slug": "compare-two-mobile",
      "title": "Two-product comparison (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for compare-two. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "compare",
        "landing",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 289
      },
      "use_cases": [
        "A/B features",
        "plan compare",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 290,
      "hex": "0x0122",
      "slug": "holy-grail",
      "title": "Holy grail (H L M R F)",
      "category": "classic",
      "description": "Classic holy-grail layout matching pane order rule exactly.",
      "tags": [
        "classic",
        "blog",
        "portal"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 60,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 802,
        "desktop_layout_id": null
      },
      "use_cases": [
        "portal home",
        "content site"
      ],
      "ascii_preview": "+----HEADER-----+\n| L | MAIN | R |\n+----FOOTER-----+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 802,
      "hex": "0x0322",
      "slug": "holy-grail-mobile",
      "title": "Holy grail (H L M R F) (mobile)",
      "category": "classic-mobile",
      "description": "Mobile stack for holy-grail. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "classic",
        "blog",
        "portal",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 290
      },
      "use_cases": [
        "portal home",
        "content site",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 291,
      "hex": "0x0123",
      "slug": "holy-grail-tall-sides",
      "title": "Holy grail full-height side rails",
      "category": "classic",
      "description": "Left and right rails extend full height; header/footer in center column.",
      "tags": [
        "classic",
        "app"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": true,
          "full_height_bottom": true,
          "default_width_pct": 18,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": true,
          "full_height_bottom": true,
          "default_width_pct": 18,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "left",
        "orientation": "vertical",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "drawer_left",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 803,
        "desktop_layout_id": null
      },
      "use_cases": [
        "portal",
        "workspace"
      ],
      "ascii_preview": "L | HEADER | R\nL | MAIN   | R\nL | FOOTER | R",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 803,
      "hex": "0x0323",
      "slug": "holy-grail-tall-sides-mobile",
      "title": "Holy grail full-height side rails (mobile)",
      "category": "classic-mobile",
      "description": "Mobile stack for holy-grail-tall-sides. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "classic",
        "app",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 291
      },
      "use_cases": [
        "portal",
        "workspace",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 292,
      "hex": "0x0124",
      "slug": "top-nav-main",
      "title": "Top navigation + main",
      "category": "classic",
      "description": "Simple site: header nav and main only.",
      "tags": [
        "classic",
        "marketing",
        "email"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "image",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 804,
        "desktop_layout_id": null
      },
      "use_cases": [
        "brochure",
        "simple site",
        "qweb"
      ],
      "ascii_preview": "+--NAV--+\n| MAIN  |",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 804,
      "hex": "0x0324",
      "slug": "top-nav-main-mobile",
      "title": "Top navigation + main (mobile)",
      "category": "classic-mobile",
      "description": "Mobile stack for top-nav-main. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "classic",
        "marketing",
        "email",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "image",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "table",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 292
      },
      "use_cases": [
        "brochure",
        "simple site",
        "qweb",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 293,
      "hex": "0x0125",
      "slug": "bottom-nav-shell",
      "title": "Bottom navigation shell",
      "category": "app",
      "description": "Main content with footer as primary nav host (mobile-app style also on desktop).",
      "tags": [
        "app",
        "mobile",
        "social"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "footer",
        "orientation": "horizontal",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "bottom_tabs",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 805,
        "desktop_layout_id": null
      },
      "use_cases": [
        "mobile app shell",
        "tabbed app"
      ],
      "ascii_preview": "|  MAIN  |\n+-TABS---+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 805,
      "hex": "0x0325",
      "slug": "bottom-nav-shell-mobile",
      "title": "Bottom navigation shell (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for bottom-nav-shell. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "mobile",
        "social",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list",
            "table"
          ]
        },
        {
          "index": 1,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav"
          ]
        }
      ],
      "nav": {
        "placement": "footer",
        "orientation": "horizontal",
        "pane_index": 1,
        "item_block_type": 2,
        "mobile_collapse": "bottom_tabs",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 293
      },
      "use_cases": [
        "mobile app shell",
        "tabbed app",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 294,
      "hex": "0x0126",
      "slug": "media-watch",
      "title": "Media player + sidebar",
      "category": "media",
      "description": "Header, wide main (player), right related list.",
      "tags": [
        "media",
        "video"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 70,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 30,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "image",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 806,
        "desktop_layout_id": null
      },
      "use_cases": [
        "video watch",
        "course lesson"
      ],
      "ascii_preview": "+--HEADER--+\n|PLAYER|REL|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 806,
      "hex": "0x0326",
      "slug": "media-watch-mobile",
      "title": "Media player + sidebar (mobile)",
      "category": "media-mobile",
      "description": "Mobile stack for media-watch. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "media",
        "video",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "image",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 294
      },
      "use_cases": [
        "video watch",
        "course lesson",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 295,
      "hex": "0x0127",
      "slug": "kanban-3",
      "title": "Kanban three columns",
      "category": "app",
      "description": "Header toolbar + three equal board columns.",
      "tags": [
        "app",
        "kanban",
        "project"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 807,
        "desktop_layout_id": null
      },
      "use_cases": [
        "task board",
        "pipeline"
      ],
      "ascii_preview": "+--TOOLBAR--+\n|TO DO|DOING|DONE|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 807,
      "hex": "0x0327",
      "slug": "kanban-3-mobile",
      "title": "Kanban three columns (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for kanban-3. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "kanban",
        "project",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 295
      },
      "use_cases": [
        "task board",
        "pipeline",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 296,
      "hex": "0x0128",
      "slug": "report-cover",
      "title": "Report cover page",
      "category": "document",
      "description": "Centered cover: large main only with generous padding (title page).",
      "tags": [
        "document",
        "report"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            10,
            15,
            10,
            15
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 808,
        "desktop_layout_id": null
      },
      "use_cases": [
        "cover",
        "title page"
      ],
      "ascii_preview": "+------------+\n|   TITLE    |\n|   PAGE     |\n+------------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 808,
      "hex": "0x0328",
      "slug": "report-cover-mobile",
      "title": "Report cover page (mobile)",
      "category": "document-mobile",
      "description": "Mobile stack for report-cover. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "document",
        "report",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            10,
            15,
            10,
            15
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 296
      },
      "use_cases": [
        "cover",
        "title page",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 297,
      "hex": "0x0129",
      "slug": "report-body",
      "title": "Report body with side notes",
      "category": "document",
      "description": "Header running title, main body, right notes/figures, footer page meta.",
      "tags": [
        "document",
        "report"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 72,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 28,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 809,
        "desktop_layout_id": null
      },
      "use_cases": [
        "annual report",
        "whitepaper"
      ],
      "ascii_preview": "+-running-title-+\n| BODY | NOTES |\n+-page-----------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 809,
      "hex": "0x0329",
      "slug": "report-body-mobile",
      "title": "Report body with side notes (mobile)",
      "category": "document-mobile",
      "description": "Mobile stack for report-body. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "document",
        "report",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 297
      },
      "use_cases": [
        "annual report",
        "whitepaper",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 298,
      "hex": "0x012A",
      "slug": "auth-card",
      "title": "Centered auth card",
      "category": "landing",
      "description": "Full main background with overlay card for sign-in (overlay last).",
      "tags": [
        "auth",
        "landing"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ],
          "notes": "background"
        },
        {
          "index": 1,
          "role": "overlay",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 36,
          "default_height_pct": 55,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            4,
            4,
            4,
            4
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ],
          "notes": "auth card"
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 810,
        "desktop_layout_id": null
      },
      "use_cases": [
        "login",
        "register",
        "reset password"
      ],
      "ascii_preview": "[ background ]\n   +AUTH CARD+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 810,
      "hex": "0x032A",
      "slug": "auth-card-mobile",
      "title": "Centered auth card (mobile)",
      "category": "landing-mobile",
      "description": "Mobile stack for auth-card. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "auth",
        "landing",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 2,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ],
          "notes": "background"
        },
        {
          "index": 1,
          "role": "overlay",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 55,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            4,
            4,
            4,
            4
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ],
          "notes": "auth card"
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 298
      },
      "use_cases": [
        "login",
        "register",
        "reset password",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 299,
      "hex": "0x012B",
      "slug": "map-content",
      "title": "Map / canvas + side panel",
      "category": "app",
      "description": "Header, main canvas, right tools/details.",
      "tags": [
        "app",
        "map",
        "design"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 72,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 28,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 811,
        "desktop_layout_id": null
      },
      "use_cases": [
        "map app",
        "canvas editor"
      ],
      "ascii_preview": "+--HEADER--+\n|MAP | TOOLS|",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 811,
      "hex": "0x032B",
      "slug": "map-content-mobile",
      "title": "Map / canvas + side panel (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for map-content. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "map",
        "design",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "right",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text",
            "table"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 299
      },
      "use_cases": [
        "map app",
        "canvas editor",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 300,
      "hex": "0x012C",
      "slug": "wizard-steps",
      "title": "Multi-step wizard",
      "category": "app",
      "description": "Header steps indicator, main step body, footer actions.",
      "tags": [
        "wizard",
        "onboarding",
        "form"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ],
          "notes": "step indicator as nav"
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ],
          "notes": "back/next actions"
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 812,
        "desktop_layout_id": null
      },
      "use_cases": [
        "checkout steps",
        "setup wizard"
      ],
      "ascii_preview": "+-STEPS-+\n| BODY  |\n+-ACTIONS+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 812,
      "hex": "0x032C",
      "slug": "wizard-steps-mobile",
      "title": "Multi-step wizard (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for wizard-steps. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "wizard",
        "onboarding",
        "form",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ],
          "notes": "step indicator as nav"
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table",
            "image"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ],
          "notes": "back/next actions"
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 300
      },
      "use_cases": [
        "checkout steps",
        "setup wizard",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 301,
      "hex": "0x012D",
      "slug": "empty-state",
      "title": "Empty state centered",
      "category": "app",
      "description": "Single main with large padding for empty/error states.",
      "tags": [
        "app",
        "empty",
        "error"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            12,
            15,
            12,
            15
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 813,
        "desktop_layout_id": null
      },
      "use_cases": [
        "no results",
        "404-like",
        "inbox zero"
      ],
      "ascii_preview": "+--------------+\n|  EMPTY/ERROR |\n+--------------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 813,
      "hex": "0x032D",
      "slug": "empty-state-mobile",
      "title": "Empty state centered (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for empty-state. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "empty",
        "error",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 1,
      "panes": [
        {
          "index": 0,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            12,
            15,
            12,
            15
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 301
      },
      "use_cases": [
        "no results",
        "404-like",
        "inbox zero",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 302,
      "hex": "0x012E",
      "slug": "qweb-marketing-full",
      "title": "QWeb marketing full chrome",
      "category": "qweb",
      "description": "Full marketing page: header nav, left promo, main, right CTA, footer.",
      "tags": [
        "qweb",
        "marketing"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "image",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "left",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 20,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 55,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 25,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 814,
        "desktop_layout_id": null
      },
      "use_cases": [
        "campaign landing",
        "product marketing"
      ],
      "ascii_preview": "+------HEADER-------+\n| L | MAIN | CTA  |\n+------FOOTER-------+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 814,
      "hex": "0x032E",
      "slug": "qweb-marketing-full-mobile",
      "title": "QWeb marketing full chrome (mobile)",
      "category": "qweb-mobile",
      "description": "Mobile stack for qweb-marketing-full. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "qweb",
        "marketing",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 5,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "image",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "image",
            "list"
          ]
        },
        {
          "index": 2,
          "role": "left",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "image",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "right",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        },
        {
          "index": 4,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 12,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "nav",
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 302
      },
      "use_cases": [
        "campaign landing",
        "product marketing",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 303,
      "hex": "0x012F",
      "slug": "legal-longform",
      "title": "Long-form legal",
      "category": "document",
      "description": "Header title, main terms, footer acceptance band.",
      "tags": [
        "legal",
        "document"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 815,
        "desktop_layout_id": null
      },
      "use_cases": [
        "terms of service",
        "privacy policy"
      ],
      "ascii_preview": "+-TITLE-+\n| TERMS |\n+-ACCEPT+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 815,
      "hex": "0x032F",
      "slug": "legal-longform-mobile",
      "title": "Long-form legal (mobile)",
      "category": "document-mobile",
      "description": "Mobile stack for legal-longform. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "legal",
        "document",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 3,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 10,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "list"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 303
      },
      "use_cases": [
        "terms of service",
        "privacy policy",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 304,
      "hex": "0x0130",
      "slug": "dual-list",
      "title": "Dual list chooser",
      "category": "app",
      "description": "Header, two main columns (available / selected).",
      "tags": [
        "app",
        "chooser"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 816,
        "desktop_layout_id": null
      },
      "use_cases": [
        "permission picker",
        "multi-select lists"
      ],
      "ascii_preview": "+-HEADER-+\n| A  | B  |\n+-FOOTER-+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 816,
      "hex": "0x0330",
      "slug": "dual-list-mobile",
      "title": "Dual list chooser (mobile)",
      "category": "app-mobile",
      "description": "Mobile stack for dual-list. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "app",
        "chooser",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 4,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "text",
            "nav"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "list",
            "text"
          ]
        },
        {
          "index": 3,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "none",
        "orientation": "horizontal",
        "pane_index": null,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 304
      },
      "use_cases": [
        "permission picker",
        "multi-select lists",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 305,
      "hex": "0x0131",
      "slug": "status-1x4",
      "title": "Status strip four KPIs",
      "category": "dashboard",
      "description": "Header + one row of four main KPI cells + optional footer.",
      "tags": [
        "dashboard",
        "kpi"
      ],
      "viewport": "desktop",
      "legacy_byte": null,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 1,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 2,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 3,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": null,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "stack",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": 817,
        "desktop_layout_id": null
      },
      "use_cases": [
        "ops dashboard",
        "executive strip"
      ],
      "ascii_preview": "+--HEADER--+\n|K|K|K|K|\n+--FOOTER--+",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    },
    {
      "id": 817,
      "hex": "0x0331",
      "slug": "status-1x4-mobile",
      "title": "Status strip four KPIs (mobile)",
      "category": "dashboard-mobile",
      "description": "Mobile stack for status-1x4. Panes reindexed single-column: header \u2192 main cells \u2192 left \u2192 right \u2192 footer \u2192 overlay.",
      "tags": [
        "dashboard",
        "kpi",
        "mobile"
      ],
      "viewport": "mobile",
      "legacy_byte": null,
      "pane_count": 6,
      "panes": [
        {
          "index": 0,
          "role": "header",
          "grid_col": 0,
          "grid_row": 0,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 8,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": true,
          "recommended_content": [
            "nav",
            "text"
          ]
        },
        {
          "index": 1,
          "role": "main",
          "grid_col": 0,
          "grid_row": 1,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 2,
          "role": "main",
          "grid_col": 0,
          "grid_row": 2,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 3,
          "role": "main",
          "grid_col": 0,
          "grid_row": 3,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 4,
          "role": "main",
          "grid_col": 0,
          "grid_row": 4,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": null,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text",
            "table"
          ]
        },
        {
          "index": 5,
          "role": "footer",
          "grid_col": 0,
          "grid_row": 5,
          "full_height_top": false,
          "full_height_bottom": false,
          "default_width_pct": 100,
          "default_height_pct": 6,
          "default_margin_pct": [
            0,
            0,
            0,
            0
          ],
          "default_padding_pct": [
            2,
            2,
            2,
            2
          ],
          "nav_host": false,
          "recommended_content": [
            "text"
          ]
        }
      ],
      "nav": {
        "placement": "header",
        "orientation": "horizontal",
        "pane_index": 0,
        "item_block_type": 2,
        "mobile_collapse": "hamburger_header",
        "notes": "Text stream: ITEM_BLOCK type=2 style_index in the nav host pane; items separated by US (0x1F); each item typically LINK_START\u2026LINK_END."
      },
      "pair": {
        "mobile_layout_id": null,
        "desktop_layout_id": 305
      },
      "use_cases": [
        "ops dashboard",
        "executive strip",
        "mobile"
      ],
      "ascii_preview": "stack: H \u2192 M\u2026 \u2192 L \u2192 R \u2192 F \u2192 O",
      "encoder_notes": "Emit STYLE_CONTAINER for each pane index in ascending order (0..pane_count-1) unless the document uses a single main pane only."
    }
  ]
}