这段不符合W3C标准的漂浮广告代码修改成支持W3C标准?

自己弄好了~
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>带关闭按钮的网页漂浮广告代码www.jzxue.com-建站学</title>
</head>
<body>
<div id="img" style="position: absolute; left: 311; top: 815;visibility :hidden;" onmouseover="clearInterval(interval)" onmouseout="interval = setInterval('changePos()', delay)" align="right">
<a href="#" target="_blank"><img border="0" src="http://www.jzxue.com/images/logo.gif"></a><br><span style="CURSOR:hand;color:red;font-weight:bold" onclick="clearInterval(interval);img.style.visibility = 'hidden'">X</span>
</div>
<script language=javascript>
var xPos = 20;//from jzxue.com
var yPos = document.documentElement.clientHeight;
var step = 1;
var delay = 30;                     
var height = 0;                     
var Hoffset = 0;                    
var Woffset = 0;                     
var yon = 0;                    
var xon = 0;                     
var pause = true;                    
var interval;                    
img.style.top = yPos;                    
function changePos() {                   
width = document.documentElement.clientWidth;                    
height = document.documentElement.clientHeight;                    
Hoffset = img.offsetHeight;                    
Woffset = img.offsetWidth;                   
img.style.left = xPos + document.documentElement.scrollLeft+"px";                    
img.style.top = yPos + document.documentElement.scrollTop+"px";                    
if (yon) {                  
yPos = yPos + step;                    
}               
else {             
yPos = yPos - step;                    
}            
if (yPos < 0) {                  
yon = 1;                    
yPos = 0;                    
}                  
if (yPos >= (height - Hoffset)) {                    
yon = 0;                    
yPos = (height - Hoffset);                     
}                  
if (xon) {                    
xPos = xPos + step;                    
}                 
else {                 
xPos = xPos - step;                   
}                  
if (xPos < 0) {                    
xon = 1;                   
xPos = 0;                   
}         
if (xPos >= (width - Woffset)) {                    
xon = 0;           
xPos = (width - Woffset);                    
}                    
}
function start() {                    
img.style.visibility = "visible";                  
interval = setInterval('changePos()', delay);                    
}              
start();  
</script>
</body>
</html>