Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (0,0) content-size 800x116 [BFC] children: not-inline
    BlockContainer <body> at (8,8) content-size 784x100 children: not-inline
      BlockContainer <div#a> at (8,8) content-size 100x100 children: not-inline
        BlockContainer <div#b> at (8,8) content-size 100x100 children: inline
          TextNode <#text>
