html,body{
	width:100%;
	height:100%
}
body{
background-color: #efefef;
/*background-image:url("https://api.dujin.org/bing/1920.php");*/
background-size: 100% 100%;
background-repeat: no-repeat; 
background-attachment: fixed; 
background-position: center 0; 
background-size: cover; 
opacity:0.8; /* 设置虚化 */
}