JavaScript实现霓虹灯文字变色效果

<!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=gb2312">
<title>霓虹灯</title>
</head>
<body>
<script>
var Tname="欢迎您的到来！";
var Tlen=Tname.length;
document.write("<div id='a' style='font-size:40px;'>"+Tname+"</div>");
var col=new Array("#FFCC00","#3333FF","#FFCC00","#FF0000","#FFCC00","#CC33FF");
var ic=0;
function Dcolor(){
 var Strname="";
 for (i=0;i<Tlen;++i){
  var Strname=Strname+"<font color="+col[ic]+">"+Tname.substring(i,i+1)+"</font>";
 ic=ic+1;
  if (ic==col.length) ic=0;
 }
 a.innerHTML=Strname;
 setTimeout("Dcolor()",200);
}
Dcolor();
</script>
<span class="style5"></span>
</body>
</html>