Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (1,1) content-size 798x99 [BFC] children: not-inline
    BlockContainer <body> at (10,10) content-size 500x81 children: not-inline
      BlockContainer <div.a> at (51,21) content-size 413x49 children: not-inline
        BlockContainer <div.b> at (92,32) content-size 326x17 children: inline
          InlineNode <span>
            frag 0 from TextNode start: 0, length: 5, rect: [93,32 39.78125x17] baseline: 13.296875
                "Hello"
            TextNode <#text>

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x101]
    PaintableWithLines (BlockContainer<BODY>) [9,9 502x83]
      PaintableWithLines (BlockContainer<DIV>.a) [10,10 500x81]
        PaintableWithLines (BlockContainer<DIV>.b) [91,31 328x19]
          PaintableWithLines (InlineNode<SPAN>)
            TextPaintable (TextNode<#text>)
