.allClassify{
    position: absolute;
    background: rgba(0,0,0,.5);
    width: 300px;
    right: 0;
    top: 98px;
    z-index: 3;
    /* bottom: 0; */
    height: 856px;
    overflow-y: scroll;
}
.allClassify ul>li{
    height: 172px;
}