.center-box {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.center-image {
    @media screen and (min-width: 768px) {
        width: 540px;
    }

    @media screen and (min-width: 992px) {
        width: 720px;
    }
}