<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
.box{
width:300px;height:300px;
/*url图片途径*/
background:url(bg3.jpg) no-repeat center; border:5px solid #0099CC;
-webkit-transition:0.5s;
background-size:500px 500px;
}
.box:hover{
background-size:600px 600px;
}
</style>
</head>
<body>
<div class="box"></div>
</body>
</html>
