<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<html>
<head>
<style>
html { margin-top: 20px; margin-left: 20px; padding: 0px;}
body { padding: 0px; margin: 0px;}
</style>
</head>
<body>
<div style="height: 100px; width: 100px; background: red;"></div>
<div style="position: absolute; top: 20px; left: 20px; height: 100px; width: 100px; background: green;"></div>
</body>
</html>