.card-img
{
    display: block;
    position: relative;
    background-color: #efefef;
    border-radius: 10px;

    margin: .5rem;
    padding: .5rem;

    padding-top: 66.66%;

    height: 0;
    overflow: hidden;
    transition: transform 0.1s ease;
}

.card-img:hover {
    transform: scale(1.1);
}

.card-img img {
    position: absolute;
    left: 50%;
    top: 50%;

    width: auto;
    height: auto;
    max-width: 90%;
    max-height: 90%;

    transform: translate(-50%, -50%);
}