* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.4);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 15px;
}

.header h1 {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stats {
    display: flex;
    gap: 20px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.stats span {
    background: var(--card-bg);
    padding: 8px 16px;
    border-radius: 20px;
    border: 1px solid var(--border-color);
}

/* Category Navigation */
.category-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 25px;
    padding: 15px;
    background: var(--card-bg);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.category-btn {
    padding: 10px 20px;
    border: 1px solid var(--border-color);
    background: transparent;
    color: var(--text-secondary);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
    font-weight: 500;
}

.category-btn:hover {
    background: var(--border-color);
    color: var(--text-primary);
    transform: translateY(-2px);
}

.category-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

/* Gallery */
.gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 15px;
    opacity: 1;
    transform: translateY(0);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.gallery.fade-out {
    opacity: 0;
    transform: translateY(20px);
}

.gallery.fade-in {
    opacity: 1;
    transform: translateY(0);
}

@media (min-width: 768px) {
    .gallery {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 20px;
    }
}

@media (min-width: 1200px) {
    .gallery {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    }
}

.gallery-item {
    position: relative;
    aspect-ratio: 1;
    border-radius: 12px;
    overflow: hidden;
    cursor: pointer;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    opacity: 0;
    transform: scale(0.9) translateY(10px);
}

.gallery-item.animate-in {
    opacity: 1;
    transform: scale(1) translateY(0);
}

.gallery-item:hover {
    transform: translateY(-5px) scale(1.02);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.gallery-item:hover img {
    transform: scale(1.1);
}

.gallery-item .category-tag {
    position: absolute;
    bottom: 10px;
    left: 10px;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    backdrop-filter: blur(10px);
}

.gallery-item .index-tag {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(99, 102, 241, 0.9);
    color: white;
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
}

/* Loading */
.loading {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px;
    color: var(--text-secondary);
}

.loading.show {
    display: flex;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 15px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.95);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.modal.show {
    display: flex;
    opacity: 1;
}

.modal-content {
    position: relative;
    max-width: 95%;
    max-height: 95%;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
}

.modal-content img {
    max-width: 100%;
    max-height: 80vh;
    object-fit: contain;
    border-radius: 8px;
    cursor: pointer;
    opacity: 0;
    transform: scale(0.95);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.modal.show .modal-content img {
    opacity: 1;
    transform: scale(1);
}

.close-btn {
    position: absolute;
    top: 20px;
    right: 20px;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    color: white;
    font-size: 28px;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.3s;
    backdrop-filter: blur(10px);
    z-index: 10;
    opacity: 0;
    transform: scale(0.8);
}

.modal.show .close-btn {
    opacity: 1;
    transform: scale(1);
    transition-delay: 0.2s;
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.1);
}

/* 底部导航栏 */
.modal-nav {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    display: flex;
    align-items: center;
    gap: 20px;
    background: rgba(0, 0, 0, 0.4);
    padding: 10px 25px;
    border-radius: 30px;
    backdrop-filter: blur(10px);
    opacity: 0;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.modal.show .modal-nav {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
    transition-delay: 0.3s;
}

.nav-btn {
    background: rgba(255, 255, 255, 0.1);
    border: none;
    color: white;
    font-size: 18px;
    width: 36px;
    height: 36px;
    cursor: pointer;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: scale(1.1);
}

.image-info {
    color: var(--text-secondary);
    font-size: 0.85rem;
    min-width: 100px;
    text-align: center;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 80px 20px;
    color: var(--text-secondary);
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.5s ease;
}

.empty-state.show {
    opacity: 1;
    transform: translateY(0);
}

.empty-state svg {
    width: 80px;
    height: 80px;
    margin-bottom: 20px;
    opacity: 0.5;
}

/* Mobile Optimizations */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }

    .header {
        flex-direction: column;
        text-align: center;
    }

    .header h1 {
        font-size: 1.4rem;
    }

    .stats {
        width: 100%;
        justify-content: center;
    }

    .category-nav {
        padding: 10px;
        gap: 8px;
    }

    .category-btn {
        padding: 8px 14px;
        font-size: 0.8rem;
    }

    .gallery {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 10px;
    }

    .modal-nav {
        padding: 8px 20px;
        gap: 15px;
    }

    .nav-btn {
        width: 32px;
        height: 32px;
        font-size: 16px;
    }

    .image-info {
        font-size: 0.8rem;
        min-width: 80px;
    }

    .close-btn {
        top: 10px;
        right: 10px;
        width: 36px;
        height: 36px;
        font-size: 24px;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-color);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}