layer at (0,0) size 800x600
  LayoutView at (0,0) size 800x600
layer at (0,0) size 800x52
  LayoutBlockFlow {HTML} at (0,0) size 800x52
    LayoutBlockFlow {BODY} at (8,16) size 784x20
      LayoutBlockFlow {P} at (0,0) size 784x20
        LayoutText {#text} at (0,0) size 381x19
          text run at (0,0) width 381: "The first line of this paragraph should have a green background."