body {
    /*width: 1024px;
    height: 1540px;
    margin: 0 auto;*/
    margin: 0px;
}

.main-img {
    width: 1054px;
    height: 2435px;
    margin: 0 auto;
    background: url(../images/20170729.png) no-repeat;
    background-position: center;
    position: relative;
}

    .main-img .a1 {
           width: 49%;
    height: 55px;
    position: absolute;
    top: 316px;
    left: 1px;
    display: block;
    }
     .main-img .a2 {
           width: 49%;
    height: 55px;
    position: absolute;
    top: 316px;
    right: 1px;
    display: block;
    }