:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-card: #ffffff;
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-muted: #999999;
    --border-color: #e1e4e8;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.15);
    --accent-primary: #8661C5;
    --accent-secondary: #6941C6;
    --success: #10b981;
    --warning: #f59e0b;
    --header-gradient: linear-gradient(135deg, #8661C5 0%, #6941C6 100%);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --bg-primary: #0d1117;
    --bg-secondary: #161b22;
    --bg-card: #1c2128;
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --text-muted: #6e7681;
    --border-color: #30363d;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.5);
    --accent-primary: #a78bfa;
    --accent-secondary: #8b5cf6;
    --success: #3fb950;
    --warning: #d29922;
    --header-gradient: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', 'Arial', sans-serif;
    line-height: 1.6;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    padding: 20px;
    transition: var(--transition);
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50px;
    padding: 8px 16px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    font-size: 0.9rem;
    color: var(--text-primary);
}

.theme-toggle:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.theme-toggle .icon {
    font-size: 1.2rem;
}

header {
    text-align: center;
    margin-bottom: 40px;
    padding: 40px 20px;
    background: var(--header-gradient);
    color: white;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, rgba(255,255,255,0.1) 0%, transparent 100%);
    pointer-events: none;
}

.header-logo {
    width: 120px;
    height: auto;
    margin: 0 auto 20px;
    display: block;
    position: relative;
    filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.3));
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 12px;
    font-weight: 700;
    position: relative;
}

header .subtitle {
    font-size: 1.1rem;
    opacity: 0.95;
    margin-bottom: 16px;
    position: relative;
}

.header-meta {
    font-size: 0.9rem;
    opacity: 0.9;
    position: relative;
}

.platform-nav {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 32px;
    flex-wrap: wrap;
}

.nav-btn {
    padding: 16px 28px;
    border: 2px solid var(--border-color);
    background: var(--bg-card);
    color: var(--text-primary);
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.05rem;
    font-weight: 600;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 14px;
}

.nav-logo {
    width: 48px;
    height: auto;
    object-fit: contain;
}

.nav-logo-chat,
.nav-logo-github {
    width: 62px;
}

.nav-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-2px);
}

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

/* Controls Bar - Search, Filters, and Quick Links */
.controls-bar {
    max-width: 1400px;
    margin: 0 auto 32px;
    background: var(--bg-card);
    border-radius: 16px;
    padding: 24px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.search-box {
    margin-bottom: 20px;
}

.search-box input {
    width: 100%;
    padding: 14px 20px;
    font-size: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 24px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: var(--transition);
    outline: none;
}

.search-box input:focus {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(134, 97, 197, 0.1);
}

.filter-sort-container {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
    margin-bottom: 20px;
}

.filter-group,
.sort-group {
    flex: 1;
    min-width: 280px;
}

.filter-group label,
.sort-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.pill-group {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.pill-btn {
    padding: 10px 18px;
    border: 2px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
    white-space: nowrap;
}

.pill-btn:hover {
    border-color: var(--accent-primary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.pill-btn.active {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
    box-shadow: 0 4px 12px rgba(134, 97, 197, 0.3);
}

.category-quick-links {
    padding-top: 16px;
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.quick-links-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.category-link {
    padding: 6px 14px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    text-decoration: none;
    border-radius: 16px;
    font-size: 0.85rem;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.category-link:hover {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
    transform: translateY(-1px);
}

.capabilities-grid {
    display: grid;
    gap: 32px;
    max-width: 1400px;
    margin: 0 auto;
}

.category {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.category:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.category h2 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 16px;
}

.feature {
    background: var(--bg-secondary);
    padding: 16px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.feature:hover {
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.feature h3 {
    font-size: 1rem;
    color: var(--text-primary);
    font-weight: 600;
}

.feature p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.feature-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 8px;
}

.badge {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge.recent {
    background: linear-gradient(135deg, var(--success) 0%, #059669 100%);
    color: white;
}

.badge.coming {
    background: linear-gradient(135deg, var(--warning) 0%, #d97706 100%);
    color: white;
}

.badge.released {
    background: linear-gradient(135deg, #6b7280 0%, #4b5563 100%);
    color: white;
}

.links {
    margin-top: auto;
    padding-top: 12px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.links a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: var(--accent-primary);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-size: 0.85rem;
    transition: var(--transition);
}

.links a:hover {
    background: var(--accent-secondary);
    transform: translateY(-1px);
}

footer {
    text-align: center;
    margin-top: 48px;
    padding: 24px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

footer a {
    color: var(--accent-primary);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .platform-nav {
        flex-direction: column;
    }
    
    .nav-btn {
        width: 100%;
    }
    
    .filter-sort-container {
        flex-direction: column;
    }
    
    .filter-group,
    .sort-group {
        min-width: 100%;
    }
    
    .pill-group {
        justify-content: center;
    }
    
    .category-quick-links {
        justify-content: center;
    }
}