.wh{
    position:relative;
    width:100%;
    min-height:1px;
    padding-right:15px;
    padding-left:15px
    
}
.mx-aut{
    margin-bottom:110px;
    
}

.wechat_qr:hover:before {
    width: 150px;
    height: 150px;
    top: 25px;
    left: 110px;
    content: "";
    position: absolute;
    background-image: url("/upload/app.png");
    background-size: 150px 150px;
}