.qd_bg {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 1px;
    left: 0;
}

.banner-cover-w {
    width: 100%;
    /*max-width: 1400px;*/
    margin-left: auto;
    margin-right: auto;
    position: relative;
    background-color: #000;
    overflow: hidden;
    margin-top: -1px;
}

.banner-cover-w::before {
    content: "";
    display: block;
    width: 1px;
    margin-left: -1px;
    padding-top: 52.95%;
}

.banner-cover {
    background-color: #000;
}