.asdf {
    background: url(https://s26162.pcdn.co/wp-content/uploads/2019/03/2b1006f192854fe512926bd3dffb1875.jpg) no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}