Så kan du skrive:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "
http://www.w3.org/TR/html4/loose.dtd"><html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>TITLE</title>
<style type="text/css">
body, html {
height: 100%;
margin: 0;
padding: 0;
border: 0;
}
</style>
<script type="text/JavaScript">
function bla(e) {
var dE, oGnu = document.getElementById("gnu");
dE = document.documentElement;
oGnu.style.left = (e.clientX+dE.scrollLeft) + "px";
oGnu.style.top = (e.clientY+dE.scrollTop) + "px";
}
</script>
</head>
<body>
<div id="gnu" style="position:absolute;background-color:red"> </div>
<div style="cursor:default" onclick="bla(event)">
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kjjk kj kj kjk jk jk jkj kjjk kj kj kjk jk jk jkj kjjk kj kj kjk jk jk jkj<br>
kjjk kj kj kjk jk jk jkj kjjk kj kj kjk jk jk jkj kjjk kj kj kjk jk jk jkj<br>
kjjk kj kj kjk jk jk jkj kjjk kj kj kjk jk jk jkj kjjk kj kj kjk jk jk jkj<br>
</div>
</body>
</html>
- og nej, det er ikke kun musens koordinater, du skal bruge ... du skal bl.a. også lære, at CSS foreskriver, du _altid_ skal have enheder på andre dimensions-værdier, der ikke har værdien 0