body{
  height: 200px;
  width: 300px;
            margin: 100px auto;
	background: url("https://cdn.luogu.com.cn/upload/image_hosting/xy6i079n.png") no-repeat  fixed !important;
  background-repeat:no-repeat ;
  background-attachment: fixed;
  background-size: cover;
  position: absolute;
  overflow: hidden;
  overflow-x: hidden;
  overflow-y: scroll;
}