ghost666,
<html>
<head>
<meta content="text/html; charset=windows-1251" http-equiv="content-type" />
<script type="text/javascript">
function findDimensions()
{
var width = document.body.clientWidth;
var height = document.body.clientHeight;
var el = document.getElementById("layer");
el.style.height = height - 30 + "px";
el.style.width = width - 500 + "px";
}
if (window.addEventListener)
window.addEventListener("load", findDimensions, false);
else if (window.attachEvent)
window.attachEvent("onload", findDimensions);
window.onresize = findDimensions;
</script>
</head>
<body>
<div id="layer" style="border:2px solid #bb0000;"></div>
</body>
</html>