用!DOCTYPE声明后，部分的JS效果无效了怎么解决啊？
!DOCTYPE代码：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
JS代码：
colours=new Array('ff0000','00ff00','3366ff','ff00ff','ffa500','ffffff','fff000')
amount=colours.length;
YgetDelay=0,XgetDelay=0,Ydelay=0,Xdelay=0,ns=(document.layers)?1:0,step=0.2,currStep=0,my=0,mx=0;
if (ns){
for (i=0; i < amount; i++)
document.write('<LAYER NAME="nsstars'+i+'" BGCOLOR='+colours[i]+' CLIP="0,0,2,2"></LAYER>');
}
else{
document.write('<div id="ie" style="position:absolute;top:0;left:0;"><div style="position:relative">');
for (i=0; i < amount; i++)
document.write('<span id="iestars" style="position:absolute;top:0;left:0;width:2px;height:2px;background:'+colours[i]+';font-size:2px"></span>');
document.write('</div></div>');
}
if (ns){
window.captureEvents(Event.MOUSEMOVE);
function nMouse(evnt){
my=evnt.pageY;mx=evnt.pageX
}
window.onMouseMove=nMouse;
}
else{
function iMouse(){
my=event.y;mx=event.x;
}
document.onmousemove=iMouse
}
function stars(){
if (!ns)ie.style.top=document.body.scrollTop;
for (i=0; i < amount; i++)
{
var layer=(document.layers)?document.layers["nsstars"+i]:iestars[i].style;
layer.top= Ydelay+100*Math.sin((5*Math.sin((currStep-15.99)/10))+i*70)*Math.sin((currStep)/10)*Math.cos((currStep+i*25)/10);
layer.left=Xdelay+180*Math.cos((5*Math.sin((currStep-15.99)/10))+i*70)*Math.sin((currStep)/10)*Math.cos((currStep+i*25)/10);
}
currStep+=step;
}
function delay(){
Ydelay = YgetDelay+=(my-YgetDelay)*1/20;
Xdelay = XgetDelay+=(mx-XgetDelay)*1/20;
stars();
setTimeout('delay()',10);
}
delay();
