/* Gallery Loading States and Performance Optimizations */

/* Loading indicator for main image */
.gallery-main-image {
    position: relative;
}

.gallery-main-image.loading::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 40px;
    height: 40px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top-color: #6a8bab;
    border-radius: 50%;
    animation: gallery-spinner 0.8s linear infinite;
    z-index: 1;
}

.gallery-main-image.loading img {
    opacity: 0.5;
    filter: blur(5px);
    transition: opacity 0.3s ease, filter 0.3s ease;
}

.gallery-main-image img {
    transition: opacity 0.3s ease, filter 0.3s ease;
    opacity: 1;
    filter: blur(0);
}

/* Loading state for thumbnails */
.gallery-thumbnail.loading {
    position: relative;
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
}

.gallery-thumbnail.loading img {
    opacity: 0;
    transition: opacity 0.3s ease;
}

.gallery-thumbnail img {
    opacity: 1;
    transition: opacity 0.3s ease;
}

/* Spinner animation */
@keyframes gallery-spinner {
    to {
        transform: translate(-50%, -50%) rotate(360deg);
    }
}

/* Shimmer effect for loading thumbnails */
@keyframes shimmer {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

/* Optimize image rendering */
.gallery-main-image img,
.gallery-thumbnail img {
    will-change: transform;
    image-rendering: -webkit-optimize-contrast;
    image-rendering: crisp-edges;
    backface-visibility: hidden;
    transform: translateZ(0);
}

/* Smooth fade-in for loaded images */
.gallery-main-image img[src] {
    animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.98);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Preload hint for browsers */
.gallery-thumbnail img {
    content-visibility: auto;
}

/* Reduce motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    .gallery-main-image.loading::before {
        animation: none;
        border: 3px solid #6a8bab;
    }
    
    .gallery-thumbnail.loading {
        animation: none;
        background: #f0f0f0;
    }
    
    .gallery-main-image img,
    .gallery-thumbnail img {
        transition: none;
    }
}