/* Optimized Gallery Styles for Britain in Pictures */

/* Masonry Gallery Layout */
.masonry-gallery {
    columns: 4;
    column-gap: 15px;
    padding: 15px;
    max-width: 100%;
    margin: 0 auto;
    min-height: 400px;
}

/* Gallery Items */
.masonry-gallery .gallery-item {
    break-inside: avoid;
    margin-bottom: 15px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    background: white;
    position: relative;
    will-change: transform;
    transform: translateZ(0); /* Hardware acceleration */
}

.masonry-gallery .gallery-item:hover {
    transform: translateY(-5px) translateZ(0);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

/* Image Styles */
.masonry-gallery .gallery-item img {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    will-change: transform;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}

.masonry-gallery .gallery-item:hover img {
    transform: scale(1.05) translateZ(0);
}

/* Caption Styles */
.masonry-gallery .gallery-item .caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(transparent, rgba(0,0,0,0.8));
    color: white;
    padding: 20px 15px 15px;
    opacity: 0;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    transform: translateY(10px) translateZ(0);
    pointer-events: none;
}

.masonry-gallery .gallery-item:hover .caption {
    opacity: 1;
    transform: translateY(0) translateZ(0);
}

.masonry-gallery .gallery-item .caption h6 {
    margin: 0 0 5px 0;
    font-weight: 600;
    font-size: 0.9rem;
    line-height: 1.3;
}

.masonry-gallery .gallery-item .caption .meta {
    font-size: 0.8rem;
    opacity: 0.9;
    margin-bottom: 8px;
}

.masonry-gallery .gallery-item .caption .stats {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 8px;
}

.masonry-gallery .gallery-item .caption .stats span {
    display: flex;
    align-items: center;
    gap: 5px;
    font-size: 0.75rem;
}

/* Loading States */
.gallery-item.loading {
    opacity: 0.6;
    pointer-events: none;
    animation: pulse 1.5s ease-in-out infinite;
}

.gallery-item.loaded {
    opacity: 1;
    animation: fadeInUp 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.gallery-item.error {
    opacity: 0.3;
    filter: grayscale(100%);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px) translateZ(0);
    }
    to {
        opacity: 1;
        transform: translateY(0) translateZ(0);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 0.6;
    }
    50% {
        opacity: 0.8;
    }
}

/* Responsive Design */
@media (max-width: 1400px) {
    .masonry-gallery {
        columns: 3;
    }
}

@media (max-width: 1200px) {
    .masonry-gallery {
        columns: 3;
        column-gap: 12px;
    }
}

@media (max-width: 768px) {
    .masonry-gallery {
        columns: 2;
        column-gap: 10px;
        padding: 10px;
    }
    
    .masonry-gallery .gallery-item {
        margin-bottom: 10px;
    }
    
    .masonry-gallery .gallery-item .caption {
        padding: 15px 10px 10px;
    }
    
    .masonry-gallery .gallery-item .caption h6 {
        font-size: 0.8rem;
    }
    
    .masonry-gallery .gallery-item .caption .meta {
        font-size: 0.7rem;
    }
    
    .masonry-gallery .gallery-item .caption .stats {
        gap: 10px;
    }
    
    .masonry-gallery .gallery-item .caption .stats span {
        font-size: 0.7rem;
    }
}

@media (max-width: 480px) {
    .masonry-gallery {
        columns: 1;
        column-gap: 8px;
        padding: 8px;
    }
    
    .masonry-gallery .gallery-item {
        margin-bottom: 8px;
    }
}

/* Performance Optimizations */
.gallery-item {
    contain: layout style paint;
}

.gallery-item img {
    contain: layout style paint;
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Loading spinner improvements */
.spinner-border {
    border-width: 0.2em;
}

/* Stats improvements */
#loadingStats {
    background: rgba(255,255,255,0.95);
    padding: 12px 24px;
    border-radius: 25px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    display: inline-block;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.2);
}

#cacheStatus {
    font-size: 0.7rem;
    padding: 3px 10px;
    border-radius: 12px;
}

/* Search highlight */
.search-highlight {
    background-color: #ffeb3b;
    padding: 2px 4px;
    border-radius: 3px;
    color: #333;
    font-weight: 600;
}

/* Focus states for accessibility */
.gallery-item:focus-within {
    outline: 2px solid #007bff;
    outline-offset: 2px;
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    .masonry-gallery .gallery-item,
    .masonry-gallery .gallery-item img,
    .masonry-gallery .gallery-item .caption {
        transition: none;
    }
    
    .gallery-item.loaded {
        animation: none;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .masonry-gallery .gallery-item {
        border: 2px solid #000;
    }
    
    .masonry-gallery .gallery-item .caption {
        background: rgba(0,0,0,0.9);
    }
}

/* Print styles */
@media print {
    .masonry-gallery {
        columns: 2;
        column-gap: 10px;
    }
    
    .masonry-gallery .gallery-item {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #ccc;
    }
    
    .masonry-gallery .gallery-item .caption {
        opacity: 1;
        background: rgba(0,0,0,0.9);
        color: white;
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    .masonry-gallery .gallery-item {
        background: #2d3748;
        box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    }
    
    .masonry-gallery .gallery-item:hover {
        box-shadow: 0 8px 25px rgba(0,0,0,0.4);
    }
    
    #loadingStats {
        background: rgba(45, 55, 72, 0.95);
        color: white;
        border: 1px solid rgba(255,255,255,0.1);
    }
}