Viewport <#document> at [0,0] [0+0+0 800 0+0+0] [0+0+0 600 0+0+0] [BFC] children: not-inline
  BlockContainer <html> at [0,0] [0+0+0 800 0+0+0] [0+0+0 52 0+0+0] [BFC] children: not-inline
    BlockContainer <body> at [8,8] [8+0+0 784 0+0+8] [8+0+0 36 0+0+8] children: not-inline
      BlockContainer <details> at [8,8] [0+0+0 784 0+0+0] [0+0+0 36 0+0+0] children: not-inline
        ListItemBox <summary> at [24,8] [0+0+0 768 0+0+0] [0+0+0 18 0+0+0] children: inline
          frag 0 from TextNode start: 0, length: 13, rect: [24,8 114.625x18] baseline: 13.796875
              "I'm a summary"
          ListItemMarkerBox <(anonymous)> at [8,13] [0+0+0 8 0+0+0] [0+0+0 8 0+0+0] children: not-inline
          TextNode <#text> (not painted)
        BlockContainer <slot> at [8,26] [0+0+0 784 0+0+0] [0+0+0 18 0+0+0] children: inline
          TextNode <#text> (not painted)
          TextNode <#text> (not painted)
          InlineNode <span> at [8,26] [0+0+0 82.3125 0+0+0] [0+0+0 18 0+0+0]
            frag 0 from TextNode start: 0, length: 10, rect: [8,26 82.3125x18] baseline: 13.796875
                "I'm a node"
            TextNode <#text> (not painted)
          TextNode <#text> (not painted)
      BlockContainer <(anonymous)> at [8,44] [0+0+0 784 0+0+0] [0+0+0 0 0+0+0] children: inline
        TextNode <#text> (not painted)

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x52]
    PaintableWithLines (BlockContainer<BODY>) [8,8 784x36]
      PaintableWithLines (BlockContainer<DETAILS>) [8,8 784x36]
        PaintableWithLines (ListItemBox<SUMMARY>) [24,8 768x18]
          MarkerPaintable (ListItemMarkerBox(anonymous)) [8,13 8x8]
          TextPaintable (TextNode<#text>)
        PaintableWithLines (BlockContainer<SLOT>) [8,26 784x18]
          PaintableWithLines (InlineNode<SPAN>) [8,26 82.3125x18]
            TextPaintable (TextNode<#text>)
      PaintableWithLines (BlockContainer(anonymous)) [8,44 784x0]

SC for Viewport<#document> [0,0 800x600] (z-index: auto)
 SC for BlockContainer<HTML> [0,0 800x52] (z-index: auto)
