/* ... existing styles ... */

.nav-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    z-index: 50;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(5px);
    transition: background 0.2s;
    font-size: 20px;
    user-select: none;
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.4);
}

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

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

/* Hide on small screens/touch devices if preferred, but user asked for "desktop, wide screen" */
@media (max-width: 768px) {
    .nav-btn {
        display: none;
    }
}