.banner{
    width: 10rem;
    height: 15.98rem;
    background:url(../images/banner.jpg)no-repeat;
    background-size: 100% 100%;
    position: relative;
    margin: 0 auto;
    .btn{
        width: 4.65rem;
        height: 1.5rem;
        position: absolute;
        top: 13.7rem;
        left: 2.7rem;
    }
}
.banner2{
    width: 10rem;
    height: 15.98rem;
    background:url(../images/banner2.jpg?v=20210324)no-repeat;
    background-size: 100% 100%;
    position: relative;
    margin: 0 auto;
    .btn{
        width: 4.65rem;
        height: 1.5rem;
        position: absolute;
        top: 13.7rem;
        left: 2.7rem;
    }
}