方法一:
<style type="text/css">
body{
background: url("./lib/background.png") no-repeat center center fixed;
/*兼容浏览器版本*/
-webkit-background-size: cover;
-o-background-size: cover;
background-size: cover;
}
</style>
方法二:
style="background: url(lib/login.png); background-size: 100% 100%; background-attachment: fixed"