JS控制页面样式

鼠标悬浮的时候改变文本框和按钮的颜色、背景图片以及链接文字的大小。
<!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=gb2312" />
<title>JS控制CSS</title>
<style type="text/css">
<!--
.txtTest {
	height: 15px;
	 200px;
	border: thin dashed #0000FF;
}
.txtOutTest {
	height: 15px;
	 200px;
	border: thin dashed #FF6600;
}
.btnSub {
	background-image:url(back1.jpg);
	height: 23px;
	 82px;
	border:0;
}
-->
</style>
<script>
	var tmr;
	function Over(){
		document.getElementById("btnSub").style.backgroundImage="url('back2.jpg')";
		clearTimeout(tmr);
	}
	function Out(){
		document.getElementById("btnSub").style.background="url('back1.jpg')";
		Overs();
	}
	function Overs(){
		document.getElementById("btnSub").style.backgroundImage="url('back1.jpg')";
		tmr = setTimeout("Outs();",500);
	}
	function Outs(){
		document.getElementById("btnSub").style.background="url('back2.jpg')";
		tmr = setTimeout("Overs()",500);
	}
</script>
</head>

<body>
<p><a href="#" style="font-size:12px;" onmouseover="this.style.fontSize='36px';" onmouseout="this.style.fontSize='12px';">这个链接可以改变大小</a></p>
<p>
  <input name="textfield" type="text" class="txtTest" id="txtTest" onmouseover="this.className='txtOutTest'" onmouseout="this.className='txtTest'" />
</p>
<p>
  <input id="btnSub" type="button" class="btnSub" value="按钮" onmouseover="Over()" onmouseout="Out()" />
</p>
</body>
</html>