:root {
    --bg-color: #1a1a1a;
    --text-color: #ffffff;
    --nav-bg: #2a2a2a;
    --nav-hover: #333333;
    --accent-color: #4a9eff;
    --border-color: rgba(255, 255, 255, 0.1);
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Noto Sans SC', sans-serif;
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.site-header {
    text-align: center;
    margin-bottom: 3rem;
}

.site-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent-color);
}

main {
    flex: 1;
}

.nav-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
    padding: 1rem;
}

.nav-item {
    background: var(--nav-bg);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.nav-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
    background: var(--nav-hover);
}

.nav-link {
    display: block;
    padding: 1.5rem;
    text-decoration: none;
    color: var(--text-color);
    height: 100%;
}

.nav-title {
    display: block;
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--accent-color);
}

.nav-description {
    display: block;
    font-size: 0.9rem;
    opacity: 0.8;
}

.site-footer {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    text-align: center;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.7);
}

.footer-links {
    margin-top: 1rem;
}

.footer-links a {
    color: var(--accent-color);
    text-decoration: none;
    transition: opacity 0.3s ease;
    padding: 0 0.5rem;
}

.footer-links a:hover {
    opacity: 0.8;
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    .nav-grid {
        grid-template-columns: 1fr;
    }
}