.main{
    width: 100%;
    height: 100%;
    position: absolute;
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    padding-top: 4.2rem;
    padding-bottom: 4rem;
    box-sizing: border-box;
    overflow: scroll;
}
.code-box{
    width: 100%;
    height: auto;
    text-align: center;
    padding-top: .5rem;
}
.btn-a{
    display: block;
    max-width: 640px;
    margin: 0 auto;
}
.code-box img.btn-img{
    width: 100%;
    max-width: 60%;
}
.code-img{
    margin-top: 1rem;
}
.tips-test{
    font-size: .6rem;
    text-align: center;
    color: #5f646e;
    margin-top: .5rem;
}
.footer{
    width: 100%;
    height: 4rem;
    line-height: 4rem;
    text-align: center;
    color: #fff;
    font-size: 1rem;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    background: #171719;
}