我什么我写的没效果？求大神帮忙！！
我什么我写的没效果？求大神帮忙！！
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
#ad{
width:960px;
margin:0 auto;
display:none;
position:relative;
overflow:hidden;
}
#content{margin:0 auto;
width:960px;
}
</style>
<script>
var oAd=document.getElementById('ad');
var oAdcon=document.getElementById('adcon');
var h=0;
var maxH=oAdcon.height;
function adDown(){
if(h<maxH){
h+=5;
oAd.style.height=h+'px';
oAd.style.display='block';
setTimeout(adDown,1);
}else{
oAd.style.height=h+'px';
oAd.style.display='block';
setTimeout(adUp,3000);
}
}
setTimeout(adDown,3000);
function adUp(){
if(h>0){
h-=5;
oAd.style.height=h+'px';
setTimeout(adUp,1);
}
}
</script>
</head>
<body>
<div id="ad">
<img id="adcon" src="img/ad.png" width='960' height='385'>
</div>
<div id='content'><img src="img/数字商品-10-23.jpg" ></div>
</body>
</html>
