自适应背景图
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
</head>
<style>
*{
margin: 0;
padding: 0;
}
body,html{
width: 100%;
height: 100%;
}
#box{
width: 100%;
height: 100%;
position: relative;
}
#img{
background: url(img/1.jpg)center;
position: absolute;
top: 0;
left: 0;
right: 0;
bottom: 0;
background-repeat: no-repeat;
background-size: cover;
}
</style>
<body>
<div id="box">
<div id="img">
</div>
</div>
</body>
</html>
