<html>
<head>
<script type="text/javascript" src="jquery-1.8.2.min.js"></script>
<script type="text/javascript">
$(function(){
$("div").mouseover(function(){
$(this).animate({"width":"320","height":"100"},100);
$(this).animate({"width":"310","height":"90"},100);
}).mouseout(function(){
$(this).animate({"width":"300","height":"80"},100);
});
});
</script>
<style type="text/css">
div{width:300px;height:80px;border-radius:8px;background:green;margin-top:10px;}
</style>
</head>
<body style="background-color:#e8e8e8;">
<div></div>
<div></div>
<div></div>
<div></div>
</body>
</html>