代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>心跳</title>
<style type="text/css">
div img{
width: 400px;
position: relative;
left: 300px;top: 300px;
animation: move .7s infinite;
}
@keyframes move{
50%{
left: 100px;top: 150px;width: 800px;height: 600px;
}
100%{
left: 300px;height: 300px;width: 400px;
}
}
</style>
</head>
<body>
<div><img src="2.jpg"></div>
</body>
</html>
原文：http://www.cnblogs.com/llz1314/p/5741071.html