                        课程
                    
                        /前端开发
                        
                            /JavaScript
                        
                        /JS动画效果

鼠标划过不运动，小伙伴们帮我看下哪里错了

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
*{margin: 0;
padding: 0;
}
ul,li{
list-style: none;
}
ul li {
width:200px;
height: 100px;
background: yellow;
margin-bottom: 20px;
}

</style>
<script>
window.onload = function()
{
var aLi=document.getElementsByTagName('li');
for(var i= 0;i< aLi.length;i++){
aLi[i].timer = null;
aLi[i].onmouseover = function(){
startMove(this,400);
}
aLi[i].onmouseout = function(){
startMove(this,200);
}
}
}
//var timer= null;
function startMove( obj , iTarget)/*obj多个参数的定义*/
{
clearInterval(obj.timer);
obj.timer = setInterval(function(){
var speed = (iTarget - obj.offsetWidth)/8;
speed = speed > 0?Math.ceil(speed):Math.floor(speed);
if(obj.offsetWidth == iTarget){
clearInterval(obj.timer);
}
else{
obj.style.Width = obj.offsetWidth + speed +'px';
}
},30)
}
</script>
</head>
<body>
<ul>
<li></li>
<li></li>
<li></li>
</ul>
</body>
</html>