.item {
    width: calc(900px/4);
    height: calc(900px/4);
    line-height: 280px;
    margin: 4%;
}
    .item:hover {
        text-decoration: none;
    }


@media screen and (max-width: 820px) {
    .item {
        width: calc(100vw/4);
        height: calc(70vh/4);
        margin: 3%;     
    }
}


@media screen and (max-width: 768px) {
    .item {
        /*width: calc(100vh/4);*/
        width:44%;
        height: calc(100vh/4);      
        /*margin-left: 28%;*/
        /*margin-left: calc(20vh/1.77);*/
    }
}