.custom-cart-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5); /* semi-transparent dark */
    z-index: 9998;
    display: none;
}

/* Your popup already has higher z-index 9999 */
.custom-cart-popup {
    position: fixed;
    top: 20%;
    left: 50%;
    transform: translateX(-50%);
    background: #a53648;
    color: white;
    padding: 20px 30px;
    z-index: 9999;
    border-radius: 8px;
    display: none;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    font-size: 16px;
}

.custom-cart-popup a {
    background-color: white;
    color: #a53648;
    padding: 7px 14px;
    font-weight: 700;
    margin-top: 30px;
    border-radius: 25px;
    display: inline-block;
}