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layer at (0,0) size 812x600
  RenderBlock {HTML} at (0,0) size 800x600 [bgcolor=#FFFFFF]
    RenderBody {BODY} at (0,0) size 800x600 [bgcolor=#000000]
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        RenderBlock {DIV} at (0,0) size 800x51
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            text run at (0,0) width 527: "This header should remain at the top of the browser window as you resize it. "
            text run at (527,0) width 199: "It can wrap to multiple lines. "
            text run at (726,0) width 73: "The center"
            text run at (0,17) width 347: "should be filled with an olive-bordered green box. "
            text run at (347,17) width 441: "It should start beneath the header, end above the footer, and fill"
            text run at (0,34) width 228: "the width of the browser window."
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            text run at (0,0) width 442: "This footer should remain at the bottom of the browser window. "
            text run at (442,0) width 280: "It can wrap to multiple lines if necessary."