Viewport <#document> at [0,0] [0+0+0 800 0+0+0] [0+0+0 600 0+0+0] children: not-inline
  BlockContainer <html> at [0,0] [0+0+0 800 0+0+0] [0+0+0 16 0+0+0] [BFC] children: not-inline
    BlockContainer <body> at [8,8] [8+0+0 784 0+0+8] [8+0+0 0 0+0+8] children: not-inline
      Box <div#box1> at [8,8] flex-container(row) [0+0+0 784 0+0+0] [0+0+0 0 0+0+0] [FFC] children: not-inline
        BlockContainer <div> at [8,8] flex-item [0+0+0 0 0+0+0] [0+0+0 0 0+0+0] [BFC] children: not-inline
          Box <div#box2> at [8,8] flex-container(row) [0+0+0 0 0+0+0] [0+0+0 0 0+0+0] [FFC] children: not-inline

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x16]
    PaintableWithLines (BlockContainer<BODY>) [8,8 784x0]
      PaintableBox (Box<DIV>#box1) [8,8 784x0]
        PaintableWithLines (BlockContainer<DIV>) [8,8 0x0]
          PaintableBox (Box<DIV>#box2) [8,8 0x0]

SC for Viewport<#document> [0,0 800x600] [children: 1] (z-index: auto)
 SC for BlockContainer<HTML> [0,0 800x16] [children: 0] (z-index: auto)
