:root {
            --bg-primary: #ffffff;
            --bg-secondary: #f8fafc;
            --bg-tertiary: #f1f5f9;
            --text-primary: #1e293b;
            --text-secondary: #475569;
            --text-muted: #94a3b8;
            --border-color: #e2e8f0;
            --accent-primary: #10b981;
            --accent-secondary: #34d399;
            --accent-light: #d1fae5;
            --nav-width: 280px;
            --content-max-width: 900px;
            --header-height: 60px;
        }

        [data-theme="dark"] {
            --bg-primary: #0f172a;
            --bg-secondary: #1e293b;
            --bg-tertiary: #334155;
            --text-primary: #f1f5f9;
            --text-secondary: #cbd5e1;
            --text-muted: #64748b;
            --border-color: #334155;
            --accent-light: #064e3b;
        }

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

        html {
            scroll-behavior: smooth;
            scroll-padding-top: calc(var(--header-height) + 20px);
        }

        body {
            font-family: 'Noto Sans SC', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            background: var(--bg-primary);
            color: var(--text-primary);
            line-height: 1.75;
            font-size: 16px;
        }

        /* Header */
        .header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            height: var(--header-height);
            background: var(--bg-primary);
            border-bottom: 1px solid var(--border-color);
            z-index: 1000;
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0 24px;
        }

        .header-logo {
            display: flex;
            align-items: center;
            gap: 12px;
            font-weight: 600;
            font-size: 18px;
            color: var(--text-primary);
            text-decoration: none;
        }

        .header-logo svg {
            width: 32px;
            height: 32px;
            flex-shrink: 0;
        }

        .header-logo .short-title {
            display: none;
        }

        .header-logo .full-title {
            display: inline;
        }

        .header-actions {
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .home-btn {
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 8px;
            color: var(--text-secondary);
            text-decoration: none;
            transition: all 0.2s;
        }

        .home-btn:hover {
            background: var(--bg-tertiary);
            color: var(--accent-primary);
        }

        .lang-toggle {
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 8px 12px;
            cursor: pointer;
            color: var(--text-secondary);
            font-size: 14px;
            font-weight: 600;
            transition: all 0.2s;
            min-width: 40px;
        }

        .lang-toggle:hover {
            background: var(--bg-tertiary);
            color: var(--accent-primary);
        }

        .lang-toggle.active {
            background: var(--accent-primary);
            color: white;
            border-color: var(--accent-primary);
        }

        .theme-toggle {
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 8px 12px;
            cursor: pointer;
            color: var(--text-secondary);
            font-size: 14px;
            display: flex;
            align-items: center;
            gap: 6px;
            transition: all 0.2s;
        }

        .theme-toggle:hover {
            background: var(--bg-tertiary);
        }

        /* Navigation */
        .nav-sidebar {
            position: fixed;
            top: var(--header-height);
            left: 0;
            width: var(--nav-width);
            height: calc(100vh - var(--header-height));
            background: var(--bg-secondary);
            border-right: 1px solid var(--border-color);
            overflow-y: auto;
            padding: 24px 16px;
            z-index: 100;
            transition: transform 0.3s ease;
        }

        .nav-title {
            font-size: 12px;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 0.05em;
            color: var(--text-muted);
            margin-bottom: 16px;
            padding: 0 12px;
        }

        .nav-list {
            list-style: none;
        }

        .nav-item {
            margin-bottom: 2px;
        }

        .nav-link {
            display: block;
            padding: 8px 12px;
            color: var(--text-secondary);
            text-decoration: none;
            font-size: 14px;
            border-radius: 6px;
            transition: all 0.2s;
        }

        .nav-link:hover {
            background: var(--bg-tertiary);
            color: var(--accent-primary);
        }

        .nav-link.active {
            background: var(--accent-light);
            color: var(--accent-primary);
            font-weight: 500;
        }

        .nav-link.sub {
            padding-left: 28px;
            font-size: 13px;
        }

        /* Mobile menu button */
        .menu-toggle {
            display: none;
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 8px;
            cursor: pointer;
            color: var(--text-secondary);
        }

        /* Main content */
        .main {
            margin-left: var(--nav-width);
            margin-top: var(--header-height);
            padding: 48px 24px;
        }

        .content {
            max-width: var(--content-max-width);
            margin: 0 auto;
        }

        h1 {
            font-size: 36px;
            font-weight: 700;
            margin-bottom: 12px;
            line-height: 1.2;
        }

        .article-title-en {
            font-size: 18px;
            color: var(--text-secondary);
            font-style: italic;
            margin-bottom: 12px;
        }

        .meta {
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            color: var(--text-muted);
            font-size: 14px;
            margin-bottom: 24px;
        }

        .source-banner {
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 16px 20px;
            margin-bottom: 28px;
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .source-banner svg {
            flex-shrink: 0;
            color: var(--accent-primary);
        }

        .source-banner span {
            color: var(--text-secondary);
            font-size: 14px;
        }

        .source-banner a {
            color: var(--accent-primary);
            text-decoration: none;
            font-weight: 600;
            margin-left: auto;
        }

        .source-banner a:hover {
            text-decoration: underline;
        }

        @media (max-width: 600px) {
            .source-banner {
                flex-direction: column;
                align-items: flex-start;
            }
            .source-banner a {
                margin-left: 0;
                margin-top: 8px;
            }
        }

        /* Authors */
        .authors {
            background: var(--bg-secondary);
            border-radius: 12px;
            padding: 20px 24px;
            margin: 24px 0;
        }

        .authors h4 {
            margin: 0 0 12px 0;
            font-size: 14px;
            color: var(--text-muted);
            text-transform: uppercase;
            letter-spacing: 0.05em;
        }

        .authors-list {
            font-size: 14px;
            color: var(--text-secondary);
            line-height: 1.8;
        }

        .affiliations {
            margin-top: 16px;
            padding-top: 16px;
            border-top: 1px solid var(--border-color);
            font-size: 13px;
            color: var(--text-muted);
        }

        .affiliations p {
            margin: 4px 0;
        }

        /* Sections */
        section {
            margin-bottom: 42px;
        }

        h2 {
            font-size: 26px;
            font-weight: 700;
            margin: 36px 0 16px 0;
            padding-top: 12px;
        }

        h3 {
            font-size: 20px;
            font-weight: 600;
            margin: 26px 0 12px 0;
        }

        h4 {
            font-size: 16px;
            font-weight: 600;
            margin: 20px 0 10px 0;
            color: var(--text-primary);
        }

        p {
            margin-bottom: 14px;
            color: var(--text-secondary);
        }

        a {
            color: var(--accent-primary);
        }

        code {
            background: var(--bg-tertiary);
            padding: 2px 6px;
            border-radius: 4px;
            font-family: 'Inter', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
            font-size: 0.9em;
        }

        pre {
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 16px 18px;
            overflow-x: auto;
            font-size: 13px;
            line-height: 1.6;
            margin: 16px 0;
        }

        pre code {
            background: transparent;
            padding: 0;
            border-radius: 0;
            font-size: inherit;
        }

        mark {
            background: rgba(250, 204, 21, 0.35);
            color: inherit;
            padding: 0 2px;
            border-radius: 3px;
        }

        [data-theme="dark"] mark {
            background: rgba(250, 204, 21, 0.25);
        }

        details {
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 14px 16px;
            margin: 18px 0 22px 0;
        }

        details summary {
            cursor: pointer;
            font-weight: 600;
            color: var(--text-primary);
        }

        details[open] summary {
            margin-bottom: 12px;
        }

        /* Lists */
        ul, ol {
            margin: 16px 0;
            padding-left: 24px;
            color: var(--text-secondary);
        }

        li {
            margin-bottom: 8px;
        }

        /* Table */
        .table-wrapper {
            overflow-x: auto;
            margin: 18px 0 24px 0;
        }

        table {
            width: 100%;
            border-collapse: collapse;
            font-size: 14px;
        }

        th, td {
            padding: 10px 12px;
            border: 1px solid var(--border-color);
            text-align: left;
            vertical-align: top;
        }

        th {
            background: var(--bg-secondary);
            font-weight: 600;
            color: var(--text-primary);
        }

        td {
            color: var(--text-secondary);
        }

        /* Figure */
        .figure {
            margin: 18px 0 22px 0;
        }

        .figure img {
            width: 100%;
            border-radius: 12px;
            border: 1px solid var(--border-color);
        }

        .figure-caption {
            margin-top: 10px;
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.6;
        }

        .figure-caption strong {
            color: var(--text-primary);
        }

        /* Progress bar */
        .progress-bar {
            position: fixed;
            top: 0;
            left: 0;
            height: 3px;
            background: var(--accent-primary);
            z-index: 1001;
            width: 0%;
            transition: width 0.1s;
        }

        /* Back to top */
        .back-to-top {
            position: fixed;
            bottom: 24px;
            right: 24px;
            width: 48px;
            height: 48px;
            background: var(--accent-primary);
            color: white;
            border: none;
            border-radius: 50%;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s;
            z-index: 1000;
        }

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

        /* Footer */
        .footer {
            margin-top: 64px;
            padding-top: 32px;
            border-top: 1px solid var(--border-color);
            font-size: 14px;
        }

        .footer-source {
            background: var(--bg-secondary);
            border-radius: 12px;
            padding: 24px;
            margin-bottom: 24px;
        }

        .footer-source h4 {
            margin: 0 0 12px 0;
            color: var(--text-primary);
            font-size: 16px;
        }

        .footer-source p {
            margin: 8px 0;
            color: var(--text-secondary);
        }

        .footer-source .original-title {
            font-style: italic;
            color: var(--text-primary);
            font-weight: 500;
        }

        .footer-source .source-link {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--accent-primary);
            color: white;
            text-decoration: none;
            padding: 10px 16px;
            border-radius: 8px;
            font-weight: 500;
            margin-top: 12px;
            font-size: 14px;
            transition: background 0.2s;
        }

        .footer-source .source-link:hover {
            background: var(--accent-secondary);
        }

        .footer-source .source-link svg {
            stroke: white;
        }

        .footer-source .credits {
            margin-top: 12px;
            font-size: 14px;
            color: var(--text-muted);
        }

        .footer-source .credits a {
            color: var(--accent-primary);
            text-decoration: none;
        }

        .footer-source .credits a:hover {
            text-decoration: underline;
        }

        .footer-copyright {
            text-align: center;
            color: var(--text-muted);
        }

        /* Responsive */
        @media (max-width: 1024px) {
            .nav-sidebar {
                transform: translateX(-100%);
            }

            .nav-sidebar.open {
                transform: translateX(0);
            }

            .menu-toggle {
                display: block;
            }

            .main {
                margin-left: 0;
            }

            .header-logo .short-title {
                display: inline;
            }

            .header-logo .full-title {
                display: none;
            }
        }