@media screen and (max-width: 991px) and (min-width: 768px) {

    .left {
        position: relative;
        float: left;
        background: white;
        width: 100%;
        padding-left: 4rem;
        padding-right: 4rem;
    }

    .right {
        width: 50%;
        background: #215092;
        text-align: center;
        background-image: url('../images/bg.jpg');
        background-size: cover;
        visibility: hidden;
    }

}