.newspaper-card:hover {
    background: #f8f9fa;
    transform: translateY(-3px);
    transition: 0.2s ease-in-out;
}
/* ✅ Navigation buttons */
.overlay-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 0, 0, 0.5);
    color: #fff;
    border: none;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    font-size: 1.6rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.2s;
    z-index: 10;
}
.overlay-btn:hover {
    background: rgba(0, 0, 0, 0.8);
}
.overlay-btn.left {
    left: 10px;
}
.overlay-btn.right {
    right: 10px;
}

/* ✅ Thumbnails */
.thumb:hover {
    transform: scale(1.05);
    box-shadow: 0 0 6px rgba(0, 0, 0, 0.3);
}
.thumb.active {
    border: 3px solid #0d6efd;
}

/* ✅ Viewer container */
#viewerContainer {
    position: relative;
    overflow: hidden;
    background: #f8f9fa;
    width: 100%;
    max-width: 900px;
    height: 85vh;
    border-radius: 10px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ✅ Page indicator */
#pageIndicator {
    position: absolute;
    bottom: 10px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0, 0, 0, 0.6);
    color: #fff;
    padding: 4px 10px;
    border-radius: 12px;
    font-size: 0.9rem;
    z-index: 11;
    user-select: none;
}

/* ✅ Responsive adjustments */
@media (max-width: 768px) {
    #viewerContainer {
        height: 75vh;
        max-width: 100%;
    }
    .overlay-btn {
        width: 40px;
        height: 40px;
        font-size: 1.3rem;
    }
    .thumb {
        height: 60px;
    }
}

/* ✅ Loading spinner */
#loadingSpinner {
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 12;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease;
}

#loadingSpinner .spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #ddd;
    border-top: 5px solid #0d6efd;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}