body {
    background: rgba(12, 100, 129, 1) url('https://images.cnblogs.com/cnblogs_com/acewzj/1542074/o_v2-a2b48d85f0042e8de80fc954d30dc9f5_hd.jpg') fixed no-repeat;
    background-position: 50% 5%; 
    background-size: cover;
}