Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (1,1) content-size 798x220 [BFC] children: not-inline
    BlockContainer <body> at (10,10) content-size 780x202 children: not-inline
      Box <div.flex> at (11,11) content-size 300x200 flex-container(row) [FFC] children: not-inline
        BlockContainer <div> at (12,12) content-size 100x20 flex-item [BFC] children: not-inline
        BlockContainer <div> at (114,12) content-size 100x20 flex-item [BFC] children: not-inline
        BlockContainer <div> at (12,95.328125) content-size 100x20 flex-item [BFC] children: not-inline
        BlockContainer <div> at (114,95.328125) content-size 100x20 flex-item [BFC] children: not-inline
        BlockContainer <div> at (12,178.65625) content-size 100x20 flex-item [BFC] children: not-inline
        BlockContainer <div> at (114,178.65625) content-size 100x20 flex-item [BFC] children: not-inline

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x222]
    PaintableWithLines (BlockContainer<BODY>) [9,9 782x204]
      PaintableBox (Box<DIV>.flex) [10,10 302x202]
        PaintableWithLines (BlockContainer<DIV>) [11,11 102x22]
        PaintableWithLines (BlockContainer<DIV>) [113,11 102x22]
        PaintableWithLines (BlockContainer<DIV>) [11,94.328125 102x22]
        PaintableWithLines (BlockContainer<DIV>) [113,94.328125 102x22]
        PaintableWithLines (BlockContainer<DIV>) [11,177.65625 102x22]
        PaintableWithLines (BlockContainer<DIV>) [113,177.65625 102x22]
