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.outer> at (8,8) content-size 200x18 flex-container(column) [FFC] children: not-inline
      BlockContainer <div.middle> at (8,8) content-size 200x18 flex-item [BFC] children: not-inline
        BlockContainer <div.inner> at (8,8) content-size 200x18 children: inline
          frag 0 from TextNode start: 0, length: 20, rect: [8,8 174.234375x18] baseline: 13.796875
              "percentages are hard"
          TextNode <#text>

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x34]
    PaintableBox (Box<BODY>.outer) [8,8 200x18]
      PaintableWithLines (BlockContainer<DIV>.middle) [8,8 200x18]
        PaintableWithLines (BlockContainer<DIV>.inner) [8,8 200x18]
          TextPaintable (TextNode<#text>)
