#bofang_box {
    height: 520px;
}

@media screen and (max-width:980px) {

    #bofang_box {
        height: 200px;
    }
}
.back-to-top{
    display: flex;
    justify-content: center;
    align-items: center;
    margin: auto 8px 0 0;
    padding: 0;
}