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<meta charset="utf-8">
<title>CSS Reference: A green box</title>
<link rel="author" title="Xidorn Quan" href="https://www.upsuper.org">
<link rel="author" title="Mozilla" href="https://www.mozilla.org">
<p>Pass if there is NO red below:</p>
<div id="ref" style="width: 100px; height: 100px; background: green"></div>