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

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --bg-main: #0f172a;
    --bg-card: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border: #334155;
    --accent: #22d3ee;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-main);
    color: var(--text-primary);
    line-height: 1.6;
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    padding: 2rem 0 1.5rem;
    text-align: center;
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.3);
    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="2" fill="rgba(255,255,255,0.1)"/></svg>');
    opacity: 0.3;
}

.header-content {
    position: relative;
    z-index: 1;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
}

.header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.25rem;
    background: linear-gradient(to right, #fff, #e0e7ff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header p {
    font-size: 1rem;
    color: #e0e7ff;
    margin-bottom: 1.25rem;
}

/* Search Box */
.search-box {
    max-width: 800px;
    margin: 0 auto 1rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    padding: 0.75rem 1.25rem;
    transition: all 0.3s ease;
}

.search-box:focus-within {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.4);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

.search-input-wrapper {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.search-icon {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.7);
}

#searchInput {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    font-size: 1rem;
    color: white;
    padding: 0.25rem;
}

#searchInput::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.search-shortcut {
    background: rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.7);
    padding: 0.25rem 0.75rem;
    border-radius: 6px;
    font-size: 0.875rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

/* Quick Navigation */
.quick-nav {
    display: flex;
    justify-content: center;
    gap: 0.75rem;
    margin: 1rem 0;
    flex-wrap: wrap;
}

.nav-chip {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 1rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    color: white;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.3s ease;
    cursor: pointer;
}

.nav-chip:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.nav-chip.active {
    background: rgba(34, 211, 238, 0.2);
    border-color: var(--accent);
    color: var(--accent);
}

.chip-icon {
    font-size: 1rem;
}

/* Stats */
.stats {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-top: 1.5rem;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    font-size: 0.9rem;
    color: #cbd5e1;
}

/* Container */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem 2rem 3rem;
}

/* Category Section */
.category-section {
    margin-bottom: 2.5rem;
    animation: fadeIn 0.5s ease;
    scroll-margin-top: 2rem;
}

.category-section.hidden {
    display: none;
}

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

.category-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border);
}

.category-icon {
    font-size: 1.5rem;
}

.category-header h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.category-count {
    background: var(--primary);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

/* Tools Grid */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.tool-card:hover::before {
    transform: scaleX(1);
}

.tool-card:hover {
    transform: translateY(-8px);
    border-color: var(--primary);
    box-shadow: 0 20px 40px rgba(99, 102, 241, 0.2);
}

.tool-card.hidden {
    display: none;
}

.tool-card a {
    text-decoration: none;
    color: inherit;
    display: block;
}

.tool-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.tool-icon {
    font-size: 2.5rem;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.3));
}

.tool-badge {
    background: var(--primary);
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-left: auto;
}

.tool-badge.new {
    background: var(--success);
}

.tool-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.tool-card p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.tool-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    background: rgba(99, 102, 241, 0.1);
    color: var(--accent);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    border: 1px solid rgba(99, 102, 241, 0.2);
}

/* No Results */
.no-results {
    text-align: center;
    padding: 4rem 2rem;
    display: none;
}

.no-results.show {
    display: block;
}

.no-results-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.no-results h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.no-results p {
    color: var(--text-secondary);
}

/* Footer */
footer {
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    padding: 3rem 0;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--accent);
}

.copyright {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    font-size: 1.5rem;
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
    transition: all 0.3s ease;
    opacity: 0;
    visibility: hidden;
    z-index: 1000;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.6);
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        padding: 1.5rem 0 1rem;
    }

    .header h1 {
        font-size: 2rem;
    }
    
    .stats {
        gap: 1.5rem;
    }
    
    .stat-number {
        font-size: 1.5rem;
    }
    
    .container {
        padding: 1.5rem 1rem 2rem;
    }
    
    .tools-grid {
        grid-template-columns: 1fr;
    }

    .back-to-top {
        bottom: 1.5rem;
        right: 1.5rem;
        width: 48px;
        height: 48px;
    }
}