.nav-down li a:hover
@media screen and (max-width: 768px) {
.index-list-box img{height:170px;}
}
.newimg{position: relative;
    display: block;
    height: 0;
    width: 100%;
    padding-top: 75%;}
.newimg img{display: block;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;}    
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