.popup {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    z-index: 9999;
    text-align: center;
}

.popup img {
    max-width: 80%;
    max-height: 80%;
    margin-top: 50px;
}

.close {
    position: absolute;
    top: 20px;
    right: 20px;
    color: #fff;
    font-size: 24px;
    cursor: pointer;
}

.scroll-btn {
    visibility: hidden;
    position: fixed;
    top: 50%;
    transform: translateY(-50%);
    font-size: 24px;
    background-color: rgba(255, 255, 255, 0.5);
    border: none;
    padding: 10px;
    cursor: pointer;
    z-index: 9999;
}

.scroll-btn-prev {
    left: 20px;
}

.scroll-btn-next {
    right: 20px;
}

.gallery-item img:hover {
    opacity: 0.7;
    transition: all 0.5s linear;
}