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

:root {
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-light: #999999;
    --bg-color: #ffffff;
    --bg-gray: #fafafa;
    --border-color: #eeeeee;
    --accent-color: #333333;
    --hover-color: #000000;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.7;
    font-weight: 400;
}

.container {
    max-width: 720px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 100;
    border-bottom: 1px solid var(--border-color);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 64px;
}

.nav-brand {
    text-decoration: none;
}

.brand-text {
    font-family: 'Noto Serif SC', serif;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 0.95rem;
    transition: color 0.3s ease;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--text-primary);
}

/* Hero Section */
.hero {
    padding: 160px 0 100px;
    text-align: center;
}

.site-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
    letter-spacing: 0.05em;
}

.site-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
}

.hero-stats {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 24px;
    font-size: 0.95rem;
    color: var(--text-light);
}

.hero-stats .stat strong {
    color: var(--text-primary);
    font-weight: 500;
}

.divider {
    color: var(--border-color);
}

/* Articles Section */
.articles {
    padding: 80px 0;
    border-top: 1px solid var(--border-color);
}

.section-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 32px;
    letter-spacing: 0.02em;
}

.articles-list {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.article-item {
    padding-bottom: 32px;
    border-bottom: 1px solid var(--border-color);
}

.article-item:last-child {
    border-bottom: none;
}

.article-date {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 8px;
    display: block;
}

.article-item h3 {
    font-size: 1.15rem;
    font-weight: 500;
    margin-bottom: 8px;
}

.article-item h3 a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.article-item h3 a:hover {
    color: var(--accent-color);
}

.article-item p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

.view-more {
    display: inline-block;
    margin-top: 32px;
    font-size: 0.95rem;
    color: var(--text-secondary);
    text-decoration: none;
    padding-bottom: 2px;
    border-bottom: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.view-more:hover {
    color: var(--text-primary);
    border-bottom-color: var(--text-primary);
}

/* Notes Section */
.notes {
    padding: 80px 0;
    background-color: var(--bg-gray);
}

.notes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 16px;
}

.note-card {
    padding: 20px;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    transition: all 0.3s ease;
}

.note-card:hover {
    border-color: var(--text-primary);
}

.note-tag {
    display: inline-block;
    font-size: 0.75rem;
    color: var(--text-light);
    margin-bottom: 12px;
}

.note-card h3 {
    font-size: 0.95rem;
    font-weight: 500;
}

.note-card h3 a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.note-card h3 a:hover {
    color: var(--accent-color);
}

/* About Section */
.about {
    padding: 80px 0;
    border-top: 1px solid var(--border-color);
}

.about-content {
    max-width: 480px;
}

.about-text p {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.8;
}

.social-links {
    display: flex;
    gap: 20px;
    margin-top: 32px;
}

.social-links a {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background-color: var(--bg-gray);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background-color: var(--text-primary);
    color: white;
}

/* Footer */
.footer {
    padding: 48px 0;
    border-top: 1px solid var(--border-color);
    background-color: var(--bg-gray);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

.copyright {
    font-size: 0.85rem;
    color: var(--text-light);
}

.record {
    font-size: 0.85rem;
}

.record a {
    color: var(--text-light);
    text-decoration: none;
    transition: color 0.3s ease;
}

.record a:hover {
    color: #0066cc;
    text-decoration: none;
}

/* Visible Animation */
section.visible {
    opacity: 1 !important;
    transform: translateY(0) !important;
}

/* Responsive */
@media (max-width: 600px) {
    .nav-menu {
        gap: 20px;
    }

    .nav-menu a {
        font-size: 0.85rem;
    }

    .site-title {
        font-size: 1.8rem;
    }

    .site-subtitle {
        font-size: 1rem;
    }

    .hero-stats {
        flex-wrap: wrap;
        gap: 16px;
    }

    .articles,
    .notes,
    .about {
        padding: 60px 0;
    }

    .section-title {
        font-size: 1.3rem;
    }

    .notes-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}