HTML/CSS/CSS Attributes and Javascript Style Properties/posTop
"posTop" Example
<head>
<script language="JavaScript">
function function1(){
myDiv.style.posTop = 500
}
</script>
</head>
<body>
<div id="myDiv"
style="background-color:#EEEEEE;
position:absolute;
width:200;
cursor:hand";
onclick="function1()">
Move your mouse here to set posTop to 500.
</div>
</body>