Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (0,0) content-size 800x34 [BFC] children: not-inline
    Box <body> at (8,8) content-size 784x18 [GFC] children: not-inline
      BlockContainer <nav> at (8,8) content-size 39.78125x18 [BFC] children: inline
        frag 0 from TextNode start: 0, length: 5, rect: [8,8 39.78125x18] baseline: 13.796875
            "Hello"
        TextNode <#text>

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x34]
    PaintableBox (Box<BODY>) [8,8 784x18]
      PaintableWithLines (BlockContainer<NAV>) [8,8 39.78125x18]
        TextPaintable (TextNode<#text>)
