.dzxx>li>a {
    overflow: hidden;
    position: relative;
    display: block;
    padding-bottom: 70.44%;
    padding-top:0;}

.dzxx>li>a>img {   
    transition: all 1s;
    width: 100%;
    transform: translate(-50%, -50%) !important;
    left: 50%;
    top: 50%;
    position: absolute;}