/* ===== 章节页面专用样式 ===== */
        .chapter-header {
            position: relative;
            min-height: 75vh;
            display: flex;
            align-items: center;
            justify-content: center;
            background: linear-gradient(135deg, #3A2F2F, #5A4A4A, #4A3F3F, #2E2525);
            background-size: 400% 400%;
            animation: gradient-shift 20s ease infinite;
            overflow: hidden;
        }

        .chapter-header::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url("data:image/svg+xml,%3Csvg width='80' height='80' viewBox='0 0 80 80' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.015'%3E%3Cpath d='M40 40c0-4 4-8 8-8s8 4 8 8-4 8-8 8-8-4-8-8zm-32-32c0-4 4-8 8-8s8 4 8 8-4 8-8 8-8-4-8-8z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
            pointer-events: none;
        }

        .chapter-header::after {
            content: '';
            position: absolute;
            bottom: -1px;
            left: 0;
            right: 0;
            height: 120px;
            background: var(--color-cream);
            clip-path: ellipse(70% 100% at 50% 100%);
        }

        .chapter-header-content {
            position: relative;
            z-index: 1;
            text-align: center;
            color: white;
            padding: var(--space-xl) var(--space-md) var(--space-lg);
            max-width: 900px;
        }

        .chapter-badge {
            display: inline-block;
            padding: 0.4rem 1.2rem;
            background: rgba(196, 167, 125, 0.2);
            border: 1px solid rgba(196, 167, 125, 0.4);
            color: var(--color-accent);
            font-size: 0.8rem;
            font-weight: 500;
            letter-spacing: 4px;
            border-radius: var(--radius-full);
            margin-bottom: var(--space-md);
        }

        .chapter-num {
            font-family: var(--font-display);
            font-size: clamp(3rem, 8vw, 5rem);
            font-weight: 900;
            opacity: 0.15;
            line-height: 1;
            margin-bottom: -20px;
            letter-spacing: 8px;
        }

        .chapter-title {
            font-family: var(--font-display);
            font-size: clamp(2rem, 5vw, 3.2rem);
            font-weight: 900;
            margin-bottom: var(--space-sm);
            letter-spacing: 8px;
            text-shadow: 0 4px 20px rgba(0,0,0,0.3);
        }

        .chapter-subtitle {
            font-size: 1.05rem;
            opacity: 0.7;
            max-width: 600px;
            margin: 0 auto var(--space-md);
            line-height: 2;
            font-weight: 300;
            letter-spacing: 1px;
        }

        .chapter-meta {
            display: flex;
            justify-content: center;
            gap: var(--space-lg);
            flex-wrap: wrap;
            font-size: 0.8rem;
            opacity: 0.5;
            letter-spacing: 1px;
        }

        .chapter-meta span {
            display: flex;
            align-items: center;
            gap: 6px;
        }

        /* ===== 章节导航条 ===== */
        .chapter-nav-bar {
            background: white;
            border-bottom: 1px solid rgba(30, 30, 36, 0.06);
            padding: var(--space-sm) 0;
            position: sticky;
            top: 72px;
            z-index: 100;
            backdrop-filter: blur(12px);
            background: rgba(255,255,255,0.95);
        }

        .chapter-nav-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 var(--space-md);
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: var(--space-sm);
        }

        .chapter-nav-links {
            display: flex;
            gap: var(--space-sm);
            align-items: center;
            flex-wrap: wrap;
        }

        .chapter-nav-links a {
            font-size: 0.8rem;
            color: var(--color-warm-gray);
            padding: 0.4rem 0.8rem;
            border-radius: var(--radius-full);
            transition: var(--transition-fast);
            white-space: nowrap;
        }

        .chapter-nav-links a:hover {
            background: rgba(44, 62, 80, 0.06);
            color: var(--color-primary);
        }

        .chapter-nav-links a.active {
            background: var(--color-primary);
            color: white;
        }

        .chapter-nav-ctrl {
            display: flex;
            gap: var(--space-xs);
        }

        .chapter-nav-ctrl a {
            display: inline-flex;
            align-items: center;
            gap: 4px;
            padding: 0.5rem 1rem;
            font-size: 0.8rem;
            border-radius: var(--radius-full);
            border: 1px solid rgba(30,30,36,0.1);
            color: var(--color-warm-gray);
            transition: var(--transition-fast);
        }

        .chapter-nav-ctrl a:hover {
            background: var(--color-primary);
            color: white;
            border-color: var(--color-primary);
        }

        .chapter-nav-ctrl a.disabled {
            opacity: 0.4;
            cursor: not-allowed;
            pointer-events: none;
        }

        /* ===== 正文容器 ===== */
        .chapter-body {
            max-width: 800px;
            margin: 0 auto;
            padding: var(--space-2xl) var(--space-md);
        }

        .chapter-section {
            margin-bottom: var(--space-2xl);
        }

        .chapter-section h2 {
            font-family: var(--font-display);
            font-size: clamp(1.4rem, 3vw, 1.8rem);
            font-weight: 700;
            color: var(--color-dark);
            margin-bottom: var(--space-md);
            letter-spacing: 3px;
            padding-bottom: var(--space-sm);
            border-bottom: 2px solid var(--color-accent);
            display: inline-block;
        }

        .chapter-section h3 {
            font-family: var(--font-display);
            font-size: 1.2rem;
            font-weight: 600;
            color: var(--color-dark);
            margin: var(--space-lg) 0 var(--space-sm);
            letter-spacing: 2px;
        }

        .chapter-section p {
            font-size: 1.02rem;
            color: var(--color-dark);
            line-height: 2.2;
            margin-bottom: var(--space-md);
            text-align: justify;
            font-weight: 300;
        }

        .chapter-section .lead {
            font-size: 1.15rem;
            color: var(--color-primary);
            line-height: 2.4;
            margin-bottom: var(--space-lg);
            font-weight: 400;
            border-left: 3px solid var(--color-accent);
            padding-left: var(--space-md);
            background: linear-gradient(90deg, rgba(196,167,125,0.06), transparent);
            padding: var(--space-md) var(--space-md);
            border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
        }

        /* ===== 插图区 ===== */
        .figure-block {
            margin: var(--space-xl) 0;
            background: white;
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-md);
            border: 1px solid rgba(30, 30, 36, 0.04);
        }

        .figure-canvas-wrap {
            position: relative;
            width: 100%;
            background: linear-gradient(135deg, #F5F0E8, #E8E0D4);
        }

        .figure-canvas {
            width: 100%;
            display: block;
        }

        .figure-caption {
            padding: var(--space-md) var(--space-lg);
            background: white;
        }

        .figure-caption h4 {
            font-family: var(--font-display);
            font-size: 1rem;
            font-weight: 600;
            color: var(--color-dark);
            margin-bottom: 4px;
            letter-spacing: 1px;
        }

        .figure-caption p {
            font-size: 0.85rem;
            color: var(--color-warm-gray);
            line-height: 1.8;
            margin: 0;
            text-align: left;
        }

        .figure-caption .figure-meta {
            display: flex;
            gap: var(--space-sm);
            margin-top: var(--space-xs);
            flex-wrap: wrap;
        }

        .figure-caption .figure-meta span {
            font-size: 0.75rem;
            color: var(--color-arthistory-primary);
            background: rgba(142, 127, 127, 0.08);
            padding: 2px 10px;
            border-radius: var(--radius-full);
        }

        /* ===== 信息卡片 ===== */
        .info-card {
            background: white;
            border-radius: var(--radius-lg);
            padding: var(--space-lg);
            margin: var(--space-lg) 0;
            border-left: 4px solid var(--color-accent);
            box-shadow: var(--shadow-sm);
        }

        .info-card h4 {
            font-family: var(--font-display);
            font-size: 1rem;
            font-weight: 600;
            color: var(--color-dark);
            margin-bottom: var(--space-sm);
            letter-spacing: 1px;
        }

        .info-card p, .info-card li {
            font-size: 0.92rem;
            color: var(--color-warm-gray);
            line-height: 2;
            font-weight: 300;
        }

        .info-card ul {
            padding-left: var(--space-md);
        }

        .info-card li {
            list-style: disc;
            margin-bottom: 4px;
        }

        /* ===== 引用块 ===== */
        .philosophy-quote {
            margin: var(--space-xl) 0;
            padding: var(--space-xl);
            background: linear-gradient(135deg, #F5F0E8, #EDE6DB);
            border-radius: var(--radius-lg);
            position: relative;
        }

        .philosophy-quote::before {
            content: '"';
            font-family: Georgia, serif;
            font-size: 5rem;
            color: var(--color-accent);
            opacity: 0.3;
            position: absolute;
            top: -10px;
            left: 20px;
            line-height: 1;
        }

        .philosophy-quote p {
            font-family: var(--font-display);
            font-size: 1.15rem;
            color: var(--color-primary);
            line-height: 2.4;
            font-style: italic;
            position: relative;
            z-index: 1;
            text-align: justify;
        }

        .philosophy-quote cite {
            display: block;
            margin-top: var(--space-sm);
            font-size: 0.85rem;
            color: var(--color-warm-gray);
            font-style: normal;
            font-weight: 500;
        }

        /* ===== 对比表格 ===== */
        .compare-table-wrap {
            overflow-x: auto;
            margin: var(--space-lg) 0;
        }

        .compare-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.9rem;
            min-width: 600px;
        }

        .compare-table th {
            background: var(--color-primary);
            color: white;
            padding: 12px 16px;
            text-align: left;
            font-weight: 500;
            letter-spacing: 1px;
            font-size: 0.85rem;
        }

        .compare-table td {
            padding: 12px 16px;
            border-bottom: 1px solid rgba(30,30,36,0.06);
            color: var(--color-dark);
            line-height: 1.8;
            font-weight: 300;
        }

        .compare-table tr:nth-child(even) {
            background: rgba(196, 167, 125, 0.03);
        }

        .compare-table tr:hover {
            background: rgba(196, 167, 125, 0.06);
        }

        /* ===== 时间线小卡片 ===== */
        .mini-timeline {
            display: flex;
            flex-direction: column;
            gap: var(--space-md);
            margin: var(--space-lg) 0;
        }

        .mini-timeline-item {
            display: flex;
            gap: var(--space-md);
            align-items: flex-start;
        }

        .mini-timeline-marker {
            width: 36px;
            height: 36px;
            border-radius: var(--radius-full);
            background: linear-gradient(135deg, var(--color-arthistory-light), var(--color-arthistory-primary));
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.75rem;
            color: white;
            font-weight: 600;
            flex-shrink: 0;
        }

        .mini-timeline-content h4 {
            font-family: var(--font-display);
            font-size: 1rem;
            font-weight: 600;
            color: var(--color-dark);
            margin-bottom: 4px;
            letter-spacing: 1px;
        }

        .mini-timeline-content p {
            font-size: 0.9rem;
            color: var(--color-warm-gray);
            line-height: 1.8;
            margin: 0;
            font-weight: 300;
        }

        .mini-timeline-content .era {
            font-size: 0.75rem;
            color: var(--color-arthistory-primary);
            font-weight: 500;
            margin-top: 4px;
            display: inline-block;
            background: rgba(142, 127, 127, 0.08);
            padding: 2px 10px;
            border-radius: var(--radius-full);
        }

        /* ===== 章节底部导航 ===== */
        .chapter-end-nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: var(--space-xl) 0;
            border-top: 1px solid rgba(30,30,36,0.08);
            margin-top: var(--space-2xl);
            flex-wrap: wrap;
            gap: var(--space-sm);
        }

        .chapter-end-nav a {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 0.8rem 1.5rem;
            border-radius: var(--radius-full);
            font-size: 0.9rem;
            transition: var(--transition-fast);
        }

        .chapter-end-nav .prev {
            border: 1.5px solid rgba(44, 62, 80, 0.2);
            color: var(--color-warm-gray);
        }

        .chapter-end-nav .prev:hover {
            background: var(--color-primary);
            color: white;
            border-color: var(--color-primary);
        }

        .chapter-end-nav .next {
            background: var(--color-primary);
            color: white;
            box-shadow: var(--shadow-md);
        }

        .chapter-end-nav .next:hover {
            background: #3a4f63;
            transform: translateY(-2px);
            box-shadow: var(--shadow-lg);
        }

        .chapter-end-nav .toc-link {
            border: 1.5px solid var(--color-accent);
            color: var(--color-accent);
        }

        .chapter-end-nav .toc-link:hover {
            background: var(--color-accent);
            color: var(--color-dark);
        }

        /* ===== 双栏布局（图文并排） ===== */
        .two-col {
            display: grid;
            grid-template-columns: 1fr;
            gap: var(--space-lg);
            margin: var(--space-lg) 0;
            align-items: start;
        }

        @media (max-width: 768px) {
            .two-col {
                grid-template-columns: 1fr;
            }

            .chapter-nav-bar {
                top: 0;
            }

            .chapter-nav-container {
                flex-direction: column;
                align-items: flex-start;
            }

            .chapter-nav-links {
                overflow-x: auto;
                width: 100%;
                padding-bottom: 4px;
            }

            .chapter-title {
                letter-spacing: 4px;
            }

            .chapter-body {
                padding: var(--space-xl) var(--space-md);
            }

            .chapter-section p {
                font-size: 0.95rem;
                line-height: 2;
            }

            .philosophy-quote {
                padding: var(--space-lg);
            }

            .philosophy-quote p {
                font-size: 1rem;
            }
        }

        /* ===== 技术图解区 ===== */
        .tech-diagram {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: var(--space-md);
            margin: var(--space-lg) 0;
        }

        @media (max-width: 768px) {
            .tech-diagram {
                grid-template-columns: 1fr;
            }
        }

        .tech-item {
            background: white;
            border-radius: var(--radius-lg);
            padding: var(--space-md);
            text-align: center;
            box-shadow: var(--shadow-sm);
            border: 1px solid rgba(30,30,36,0.04);
        }

        .tech-item canvas {
            width: 100%;
            height: 120px;
            margin-bottom: var(--space-sm);
        }

        .tech-item h5 {
            font-family: var(--font-display);
            font-size: 0.95rem;
            font-weight: 600;
            color: var(--color-dark);
            margin-bottom: 4px;
            letter-spacing: 1px;
        }

        .tech-item p {
            font-size: 0.82rem;
            color: var(--color-warm-gray);
            line-height: 1.7;
            margin: 0;
            text-align: center;
        }