1_行为与样式分离

HTML代码：

1 <div id="box"></div>

CSS代码：

1 #box{ width:100px; height:100px; background:#99C;}

JS代码：

 1 window.onload=function(){
 2     var one=document.getElementById(‘box‘);
 3     one.onmouseover=toRed;
 4     one.onmouseout=toBlue;
 5     }
 6 function toRed(){
 7     var oDiv=document.getElementById(‘box‘);
 8     two.style.width="200px";
 9     two.style.height="200px";
10     two.style.background="red";}
11 function toBlue(){
12     var oDiv=document.getElementById(‘box‘);
13     two.style.width="100px";
14     two.style.height="100px";
15     two.style.background="#99c";}