@media (min-width: 1025px) {
    /*.contentDiv {
        background-color: grey;
    }*/
    .mainDiv{
        -webkit-box-shadow: 0px 2px 4px 2px rgba(0,0,0,0.75);
-moz-box-shadow: 0px 2px 4px 2px rgba(0,0,0,0.75);
box-shadow: 0px 2px 4px 2px rgba(0,0,0,0.75);
    }
}