@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&display=swap');

:root {
    --bg-color: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.85);
    --card-header-bg: rgba(51, 65, 85, 0.6);
    --text-primary: #f1f5f9;
    --text-secondary: #e2e8f0;
    --text-muted: #94a3b8;
    --text-footer: #475569;
    --accent-blue: #3b82f6;
    --accent-purple: #8b5cf6;
    --link-color: #60a5fa;
    --link-hover: #93bbfd;
    --link-visited: #a78bfa;
    --border-color: rgba(148, 163, 184, 0.12);
    --transition-speed: 0.2s;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-secondary);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    text-align: center;
    padding: 2rem 1rem 1rem;
}

header .logo img {
    vertical-align: middle;
    filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.4));
}

.logo-link {
    display: inline-block;
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary) !important;
    text-decoration: none !important;
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
    transition: opacity var(--transition-speed) ease;
}

.logo-link:hover {
    opacity: 0.8;
    text-decoration: none !important;
}

.main-content {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1.5rem;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.25rem;
    flex: 1;
}

.main-content-single {
    max-width: 400px;
    margin: 0 auto;
    padding: 1.5rem;
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.25rem;
}

.category {
    background: var(--card-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 0;
    overflow: hidden;
    transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
}

.category:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}

.category h2 {
    margin: 0;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-muted);
    text-align: center;
    background: var(--card-header-bg);
    padding: 0.75rem 1rem;
    border-bottom: 1px solid rgba(148, 163, 184, 0.1);
}

.link-list {
    list-style: none;
    padding: 0.5rem 1rem;
    margin: 0;
}

.link-list li {
    margin: 0;
    padding: 0.4rem 0.5rem;
    text-align: center;
    border-radius: 6px;
    transition: background 0.15s ease;
}

.link-list li:hover {
    background: rgba(148, 163, 184, 0.08);
}

.link-list .multi-link {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
}

footer {
    text-align: center;
    padding: 2rem 1rem;
    color: var(--text-footer);
    font-size: 0.8rem;
}

/* Links */
a {
    color: var(--link-color);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 400;
    transition: color 0.15s ease;
}

a:hover {
    color: var(--link-hover);
    text-decoration: underline;
}

a:active {
    color: var(--accent-blue);
}

a:visited {
    color: var(--link-visited);
}

/* Responsive */
@media (max-width: 640px) {
    .main-content {
        grid-template-columns: 1fr;
        padding: 1rem;
    }

    header {
        padding: 1.5rem 1rem 0.5rem;
    }
}