body{
background-image: url("https://images.cnblogs.com/cnblogs_com/beSunshine/1628340/o_2019-06-22%20135006.jpg"); background-position: initial; background-size: cover; background-repeat: no-repeat; background-attachment: fixed; background-origin: initial; background-clip: initial;
height:100%;
width:100%;
}