<!DOCTYPE html> <html> <meta charset="UTF-8"> <title>CSS Position Reference: Box inset properties & position:fixed root element</title> <link rel="author" title="Daniel Holbert" href="mailto:dholbert@mozilla.com"/> <link rel="author" title="Ting-Yu Lin" href="mailto:tlin@mozilla.com"> <link rel="author" title="Mozilla" href="http://www.mozilla.org/"> <style> html { display: block; position: fixed; left: 10px; right: 20px; top: 30px; bottom: 40px; border: 5px dashed black; box-sizing: border-box; } </style> The black border should encompass the whole viewport, with a bit of space on each side. <br><br> It shouldn't just shrinkwrap this text's height. </html>