.product-image-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    z-index: 9999;
    display: none;
}

.product-image-overlay .product-image-overlay-close {
    display: block;
    position: absolute;
    top: 20px;
    left: 20px;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 1px solid #eee;
    line-height: 35px;
    font-size: 20px;
    color: #eee;
    text-align: center;
    cursor: pointer;
}

.product-image-overlay img {
    width: auto;
    max-width: 80%;
    position: absolute;
    top: 50%;
    left: 50%;
    -webkit-transform: translate(-50%, -50%);
    -moz-transform: translate(-50%, -50%);
    -o-transform: translate(-50%, -50%);
    transform: translate(-50%, -50%);
}