body {
    background-color: #efefef;
    background-image: url(https://images.cnblogs.com/cnblogs_com/xyll1/1640095/o_200201064617734c4b45ly1g4i7nzj8yaj20pz0xhnlf.jpg);
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-position: center 0;
   
    padding-top: 0px;
    opacity: 0.8;