:root {
    --bg-primary: #FDF8F3;
    --bg-secondary: #FAF3EB;
    --text-primary: #3D3229;
    --text-secondary: #6B5A4B;
    --text-muted: #9A8A7A;
    --accent: #D4845A;
    --accent-light: #E8B08A;
    --border-color: #E8DFD5;
    --card-bg: #FFFFFF;
    --card-shadow: 0 2px 12px rgba(61, 50, 41, 0.06);
    --card-shadow-hover: 0 8px 24px rgba(61, 50, 41, 0.12);
}

[data-theme="dark"] {
    --bg-primary: #1C1611;
    --bg-secondary: #272019;
    --text-primary: #E8DFD5;
    --text-secondary: #BBA894;
    --text-muted: #8B7A68;
    --accent: #E8B08A;
    --accent-light: #D4845A;
    --border-color: #3D3229;
    --card-bg: #272019;
    --card-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
    --card-shadow-hover: 0 8px 24px rgba(0, 0, 0, 0.4);
}

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

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.8;
    transition: background-color 0.3s ease, color 0.3s ease;
    -webkit-overflow-scrolling: touch;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Noto Serif SC', serif;
    font-weight: 600;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 24px;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: baseline;
    gap: 8px;
}

.logo-text {
    font-family: 'Noto Serif SC', serif;
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-sub {
    font-size: 14px;
    color: var(--text-muted);
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.search-box {
    position: relative;
    display: flex;
    align-items: center;
}

.search-box input {
    width: 200px;
    padding: 10px 36px 10px 16px;
    border: 1px solid var(--border-color);
    border-radius: 24px;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 14px;
    transition: all 0.3s ease;
    outline: none;
}

.search-box input:focus {
    border-color: var(--accent);
    width: 240px;
}

.search-box input::placeholder {
    color: var(--text-muted);
}

.search-icon {
    position: absolute;
    right: 12px;
    color: var(--text-muted);
}

.theme-toggle {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.theme-toggle .sun-icon {
    display: block;
}

.theme-toggle .moon-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .sun-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .moon-icon {
    display: block;
}

/* Hero */
.hero {
    padding: 80px 24px 60px;
    text-align: center;
}

.hero-content {
    max-width: 600px;
    margin: 0 auto;
}

.hero-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 56px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 12px;
    margin-bottom: 12px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.hero-divider {
    width: 60px;
    height: 2px;
    background-color: var(--accent);
    margin: 0 auto 24px;
}

.hero-desc {
    font-size: 16px;
    color: var(--text-muted);
    line-height: 1.8;
}

/* Filters */
.filters {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border-color);
}

.category-tabs {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.tab {
    padding: 8px 20px;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    background-color: transparent;
    color: var(--text-secondary);
    font-size: 14px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.tab:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.tab.active {
    background-color: var(--accent);
    border-color: var(--accent);
    color: #FFFFFF;
}

.article-count {
    font-size: 14px;
    color: var(--text-muted);
}

/* Articles Grid */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
    margin-bottom: 60px;
}

.article-card {
    background-color: var(--card-bg);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--card-shadow);
    cursor: pointer;
    transition: all 0.3s ease;
}

.article-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--card-shadow-hover);
}

.article-card-cover {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.article-card:hover .article-card-cover {
    transform: scale(1.02);
}

.article-card-content {
    padding: 20px;
}

.article-card-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.article-card-category {
    padding: 4px 12px;
    background-color: var(--bg-secondary);
    color: var(--accent);
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

.article-card-date {
    font-size: 12px;
    color: var(--text-muted);
}

.article-card-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 20px;
    color: var(--text-primary);
    margin-bottom: 12px;
    line-height: 1.5;
    transition: color 0.3s ease;
}

.article-card:hover .article-card-title {
    color: var(--accent);
}

.article-card-summary {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 200;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal.active {
    opacity: 1;
    visibility: visible;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    width: 90%;
    max-width: 700px;
    max-height: 90vh;
    margin: 5vh auto;
    background-color: var(--bg-primary);
    border-radius: 16px;
    overflow-y: auto;
    transform: translateY(20px);
    transition: transform 0.3s ease;
}

.modal.active .modal-content {
    transform: translateY(0);
}

.modal-close {
    position: sticky;
    top: 16px;
    right: 16px;
    margin-left: auto;
    display: flex;
    width: 40px;
    height: 40px;
    align-items: center;
    justify-content: center;
    border: none;
    background-color: var(--bg-secondary);
    border-radius: 50%;
    color: var(--text-primary);
    cursor: pointer;
    z-index: 10;
    transition: all 0.3s ease;
}

.modal-close:hover {
    background-color: var(--accent);
    color: #FFFFFF;
}

/* Article Detail */
.article-detail {
    padding: 0 40px 40px;
}

.article-detail-cover {
    width: calc(100% + 80px);
    height: 280px;
    object-fit: cover;
    margin: 0 -40px 32px;
}

.article-detail-header {
    margin-bottom: 32px;
}

.article-detail-category {
    padding: 4px 12px;
    background-color: var(--bg-secondary);
    color: var(--accent);
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
    margin-right: 12px;
}

.article-detail-date {
    font-size: 14px;
    color: var(--text-muted);
}

.article-detail-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 32px;
    color: var(--text-primary);
    margin: 16px 0;
    line-height: 1.5;
}

.article-detail-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
}

.read-time {
    font-size: 14px;
    color: var(--text-muted);
}

.article-tags {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.article-tags span {
    padding: 4px 10px;
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    border-radius: 8px;
    font-size: 12px;
}

.article-detail-body {
    font-size: 17px;
    line-height: 2;
    color: var(--text-primary);
}

.article-detail-body p {
    margin-bottom: 20px;
    text-indent: 2em;
}

/* Back to Top */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--card-shadow);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s ease;
    z-index: 50;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    border-color: var(--accent);
    color: var(--accent);
    transform: translateY(-2px);
}

/* Empty State */
.empty-state {
    grid-column: 1 / -1;
    text-align: center;
    padding: 60px 0;
}

.empty-title {
    font-size: 18px;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.empty-desc {
    font-size: 14px;
    color: var(--text-muted);
}

/* Footer */
.footer {
    background-color: var(--bg-secondary);
    padding: 48px 24px;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1000px;
    margin: 0 auto;
}

.footer-about h3 {
    font-size: 18px;
    margin-bottom: 8px;
}

.footer-about p {
    font-size: 14px;
    color: var(--text-secondary);
    max-width: 300px;
}

.footer-copyright {
    text-align: right;
}

.footer-copyright p {
    font-size: 14px;
    color: var(--text-secondary);
}

.footer-quote {
    font-family: 'Noto Serif SC', serif;
    font-style: italic;
    color: var(--accent) !important;
    margin-top: 8px;
}

.footer-beian {
    margin-top: 12px;
    font-size: 13px;
}

.footer-beian a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

/* Responsive */
@media (max-width: 768px) {
    .hero {
        padding: 60px 24px 40px;
    }

    .hero-title {
        font-size: clamp(32px, 10vw, 48px);
        letter-spacing: 6px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .filters {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }

    .articles-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .article-card-cover {
        height: 180px;
    }

    .article-detail {
        padding: 0 24px 24px;
    }

    .article-detail-cover {
        width: calc(100% + 48px);
        height: 200px;
        margin: 0 -24px 24px;
    }

    .article-detail-title {
        font-size: 24px;
    }

    .article-detail-body {
        font-size: 16px;
        line-height: 1.9;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 24px;
    }

    .footer-copyright {
        text-align: center;
    }

    .nav {
        padding: 12px 16px;
    }

    .search-box input {
        width: 140px;
    }

    .search-box input:focus {
        width: 180px;
    }

    .logo-sub {
        display: none;
    }

    .back-to-top {
        bottom: 24px;
        right: 24px;
        width: 44px;
        height: 44px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .tab {
        padding: 6px 14px;
        font-size: 13px;
    }

    .article-card-content {
        padding: 16px;
    }

    .article-card-title {
        font-size: 18px;
    }
}