<!DOCTYPE html>
<html >
<head>
<meta charset="UTF-8">
<title>Document</title>
<style type="text/css">
body {
margin: 0;
}
img {
display: block;
width: 100%;
}
@keyframes snow{
0% {
background-position: 0 0, 0 0;
}
100% {
background-position: 500px 500px, 1000px 500px;
}
}
#snowMask {
position: fixed;
left: 0;
top: 0;
width: 100%;
height: 100%;
background: url('snow1.png'),url('snow2.png');
animation: 10s snow linear infinite;
pointer-events: none;
}
</style>
</head>
<body>
<img src="bg.jpg">
<img src="bg.jpg">
<a href="http://www.baidu.com" target="_blank" rel="external nofollow" >百度</a>
<div id="snowMask"></div>
</body>
</html>
![關于:first-child的誤區[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)