想通过改变滤镜实现炽热文字效果，为啥没反应？
程序代码：<html>
<head>
<style type="text/css">
<!--
#glowtext
{filter:glow(color=red,strength=2;width:100%;}
-->
</style>
<script language="javascript">
function golwIt(which)
{
if(document.all.glowtext[which].filters[0].strength==2)
{document.all.golwtext[which].filters[0].strength=1;}
else
{document.all.glowtext[which].filters[0].strength=2;}
}
function golwIt2()
{
if(document.all.glowtext.filters[0].strength==2)
document.all.golwtext.filters[0].strength=1;
else
document.all.glowtext.filters[0].strength=2;
}
function startGlowing()
{
if(document.all.glowtext&&glowtext.lenght)
{
for(i=0;i<glowtext.length;i++)
setInterval("glowIt(i)",150);
}
else if(glowtext)
setInterval("glowIt2()",150);
}
if(document.all)
window.onload=startGlowing;
</script>
</head>
<body>
<span id="glowtext" >我是中国人！</span>
</body>
</html>想通过改变滤镜实现炽热文字效果，为啥没反应？
