.main {
    width: 100%;
    height: 840px;
    background: url(../xzy_images/bg.png) no-repeat;
    background-position: center;
    background-size: cover;
    position: relative;
    
}
.down_load {
    position: absolute;
    top: 52%;
    left: 18%;
    display: flex;
    margin-left: -20px;

}
.down_load a {
    margin-left: 20px;
    display: block
}