/* =====================================================
   CSS Variables & Reset
   ===================================================== */

:root {
    /* Colors */
    --primary-color: #8B5CF6;
    --primary-dark: #7C3AED;
    --primary-light: #A78BFA;
    --secondary-color: #EC4899;
    --accent-color: #F59E0B;
    
    --bg-primary: #FAFAF9;
    --bg-secondary: #FFFFFF;
    --bg-tertiary: #F5F5F4;
    
    --text-primary: #1C1917;
    --text-secondary: #57534E;
    --text-tertiary: #78716C;
    
    --border-color: #E7E5E4;
    --border-light: #F5F5F4;
    
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
    
    /* Typography */
    --font-display: 'Playfair Display', serif;
    --font-body: 'Inter', sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
}

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

body {
    font-family: var(--font-body);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* =====================================================
   Loading Screen
   ===================================================== */

.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

.loading-screen.hidden {
    opacity: 0;
    visibility: hidden;
}

.loading-content {
    text-align: center;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

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

.loading-content p {
    color: var(--text-secondary);
    font-weight: 500;
}

/* =====================================================
   Header
   ===================================================== */

.header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: var(--spacing-3xl) 0 var(--spacing-2xl);
    position: relative;
    overflow: hidden;
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><circle cx="50" cy="50" r="40" fill="rgba(255,255,255,0.05)"/></svg>');
    opacity: 0.3;
}

.header-content {
    position: relative;
    z-index: 1;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
}

.logo-section {
    flex: 1;
    min-width: 300px;
}

.site-title {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    line-height: 1.2;
}

.site-subtitle {
    font-size: 1.125rem;
    opacity: 0.95;
    font-weight: 300;
}

.header-stats {
    display: flex;
    gap: var(--spacing-xl);
}

.stat-item {
    text-align: center;
    background: rgba(255, 255, 255, 0.15);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
    min-width: 100px;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    line-height: 1;
    margin-bottom: var(--spacing-xs);
}

.stat-label {
    font-size: 0.875rem;
    opacity: 0.9;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* =====================================================
   Navigation Bar
   ===================================================== */

.nav-bar {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
    transition: all var(--transition-base);
}

.nav-bar.sticky {
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-md);
}

.nav-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.nav-controls {
    display: flex;
    gap: var(--spacing-sm);
}

.search-container {
    flex: 1;
    min-width: 250px;
    max-width: 400px;
    position: relative;
}

.search-input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-xl) var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    transition: all var(--transition-base);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.1);
}

.search-btn {
    position: absolute;
    right: var(--spacing-xs);
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    padding: var(--spacing-sm);
    cursor: pointer;
    color: var(--text-tertiary);
    transition: color var(--transition-fast);
}

.search-btn:hover {
    color: var(--primary-color);
}

/* =====================================================
   Buttons
   ===================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-base);
    white-space: nowrap;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-primary.active {
    background: var(--primary-dark);
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: var(--border-color);
    transform: translateY(-1px);
}

.btn-secondary.active {
    background: var(--primary-light);
    color: white;
}

.btn-text {
    background: none;
    border: none;
    color: var(--primary-color);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 500;
    cursor: pointer;
    padding: var(--spacing-xs);
    transition: color var(--transition-fast);
}

.btn-text:hover {
    color: var(--primary-dark);
    text-decoration: underline;
}

/* =====================================================
   Filter Panel
   ===================================================== */

.filter-panel {
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg) 0;
    transition: all var(--transition-base);
    max-height: 500px;
    overflow: hidden;
}

.filter-panel.hidden {
    max-height: 0;
    padding: 0;
    opacity: 0;
}

.filter-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.filter-header h3 {
    font-family: var(--font-display);
    font-size: 1.25rem;
    color: var(--text-primary);
}

.category-filters {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.category-tag {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-md);
    background: white;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-base);
    text-transform: capitalize;
}

.category-tag:hover {
    border-color: var(--primary-light);
    background: var(--bg-primary);
}

.category-tag.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* =====================================================
   Year Navigation
   ===================================================== */

.year-navigation {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
    transition: all var(--transition-base);
    max-height: 100px;
    overflow: hidden;
}

.year-navigation.hidden {
    max-height: 0;
    padding: 0;
    opacity: 0;
}

.year-nav-scroll {
    display: flex;
    gap: var(--spacing-sm);
    overflow-x: auto;
    padding-bottom: var(--spacing-xs);
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.year-nav-scroll::-webkit-scrollbar {
    height: 6px;
}

.year-nav-scroll::-webkit-scrollbar-track {
    background: transparent;
}

.year-nav-scroll::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.year-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    white-space: nowrap;
    flex-shrink: 0;
}

.year-btn:hover {
    background: var(--bg-secondary);
    border-color: var(--primary-light);
}

.year-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* =====================================================
   Main Content & Timeline
   ===================================================== */

.main-content {
    padding: var(--spacing-2xl) 0 var(--spacing-3xl);
    min-height: 60vh;
}

.timeline-container {
    position: relative;
}

.year-section {
    margin-bottom: var(--spacing-3xl);
}

.year-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.year-header h2 {
    font-family: var(--font-display);
    font-size: 2rem;
    color: var(--primary-color);
    font-weight: 700;
}

.year-divider {
    flex: 1;
    height: 2px;
    background: linear-gradient(to right, var(--primary-color), transparent);
}

.event-count {
    font-size: 0.875rem;
    color: var(--text-tertiary);
    font-weight: 500;
}

.events-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--spacing-lg);
}

/* =====================================================
   Event Cards
   ===================================================== */

.event-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
    cursor: pointer;
    border: 1px solid var(--border-light);
}

.event-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.event-image {
    width: 100%;
    height: 240px;
    object-fit: cover;
    background: var(--bg-tertiary);
}

.event-content {
    padding: var(--spacing-lg);
}

.event-date {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
}

.event-date svg {
    width: 16px;
    height: 16px;
    opacity: 0.6;
}

.event-description {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.event-keywords {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-md);
}

.keyword-badge {
    padding: 0.25rem 0.5rem;
    background: var(--bg-tertiary);
    color: var(--text-tertiary);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    text-transform: capitalize;
}

/* =====================================================
   Modal
   ===================================================== */

.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
    transition: opacity var(--transition-base), visibility var(--transition-base);
}

.modal.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    max-width: 800px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
    animation: modalSlideIn var(--transition-slow);
}

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

.modal-close {
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    background: rgba(0, 0, 0, 0.5);
    color: white;
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    z-index: 10;
}

.modal-close:hover {
    background: rgba(0, 0, 0, 0.7);
    transform: rotate(90deg);
}

.modal-body {
    padding: var(--spacing-2xl);
}

.modal-image {
    width: 100%;
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-xl);
}

.modal-date {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    font-size: 0.9375rem;
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: var(--spacing-lg);
}

.modal-description {
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xl);
}

.modal-keywords {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.modal-keywords .keyword-badge {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.875rem;
}

/* =====================================================
   No Results
   ===================================================== */

.no-results {
    text-align: center;
    padding: var(--spacing-3xl) var(--spacing-lg);
    transition: all var(--transition-base);
}

.no-results.hidden {
    display: none;
}

.no-results-content svg {
    margin-bottom: var(--spacing-lg);
    color: var(--text-tertiary);
}

.no-results-content h3 {
    font-family: var(--font-display);
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.no-results-content p {
    color: var(--text-tertiary);
    font-size: 1rem;
}

/* =====================================================
   Footer
   ===================================================== */

.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-2xl) 0;
    text-align: center;
}

.footer-content p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.footer-years {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: var(--spacing-md) 0;
}

.footer-note {
    font-style: italic;
    color: var(--text-tertiary);
    font-size: 0.875rem;
}

/* =====================================================
   Responsive Design
   ===================================================== */

@media (max-width: 768px) {
    .site-title {
        font-size: 1.75rem;
    }
    
    .site-subtitle {
        font-size: 1rem;
    }
    
    .header-content {
        flex-direction: column;
        text-align: center;
    }
    
    .logo-section {
        min-width: auto;
    }
    
    .header-stats {
        width: 100%;
        justify-content: center;
    }
    
    .nav-content {
        flex-direction: column;
        align-items: stretch;
    }
    
    .nav-controls {
        width: 100%;
        justify-content: space-between;
    }
    
    .search-container {
        max-width: none;
    }
    
    .events-grid {
        grid-template-columns: 1fr;
    }
    
    .year-header h2 {
        font-size: 1.5rem;
    }
    
    .modal-body {
        padding: var(--spacing-lg);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .header {
        padding: var(--spacing-xl) 0 var(--spacing-lg);
    }
    
    .stat-item {
        min-width: 80px;
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .stat-number {
        font-size: 1.5rem;
    }
}

/* =====================================================
   Utilities
   ===================================================== */

.hidden {
    display: none !important;
}

.fade-in {
    animation: fadeIn var(--transition-slow);
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}