:root {
            --primary: #4f46e5;
            --secondary: #fbbf24;
            --accent: #10b981;
            --dark: #1f2937;
            --light: #f9fafb;
            --gray: #6b7280;
            --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
            --radius: 8px;
            --transition: all 0.3s ease;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }
        body {
            font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
            line-height: 1.7;
            color: var(--dark);
            background-color: var(--light);
            overflow-x: hidden;
        }
        a {
            color: inherit;
            text-decoration: none;
            transition: var(--transition);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        .header {
            background: white;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 15px 0;
        }
        .logo {
            font-size: 2rem;
            font-weight: 800;
            color: var(--primary);
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .logo i {
            color: var(--secondary);
        }
        .search-form {
            display: flex;
            flex: 0 1 400px;
        }
        .search-input {
            flex-grow: 1;
            padding: 10px 15px;
            border: 2px solid #e5e7eb;
            border-radius: var(--radius) 0 0 var(--radius);
            font-size: 1rem;
            outline: none;
        }
        .search-input:focus {
            border-color: var(--primary);
        }
        .search-btn {
            background: var(--primary);
            color: white;
            border: none;
            padding: 0 20px;
            border-radius: 0 var(--radius) var(--radius) 0;
            cursor: pointer;
            transition: var(--transition);
        }
        .search-btn:hover {
            background: #4338ca;
        }
        .mobile-toggle {
            display: none;
            background: none;
            border: none;
            font-size: 1.5rem;
            color: var(--dark);
            cursor: pointer;
        }
        .nav {
            background: var(--dark);
            padding: 0 20px;
        }
        .nav-list {
            display: flex;
            list-style: none;
        }
        .nav-item {
            position: relative;
        }
        .nav-link {
            color: white;
            padding: 15px 20px;
            display: block;
            font-weight: 500;
        }
        .nav-link:hover,
        .nav-link.active {
            background: var(--primary);
            color: white;
        }
        .breadcrumb {
            background: #f3f4f6;
            padding: 12px 20px;
            font-size: 0.9rem;
        }
        .breadcrumb-list {
            display: flex;
            list-style: none;
            gap: 8px;
        }
        .breadcrumb-item:not(:last-child)::after {
            content: ">";
            margin-left: 8px;
            color: var(--gray);
        }
        .main {
            padding: 40px 0;
        }
        .article-header {
            margin-bottom: 40px;
            text-align: center;
            padding: 30px;
            background: linear-gradient(135deg, var(--primary), #6366f1);
            color: white;
            border-radius: var(--radius);
        }
        .article-title {
            font-size: 2.8rem;
            margin-bottom: 15px;
            line-height: 1.2;
        }
        .article-meta {
            display: flex;
            justify-content: center;
            gap: 20px;
            font-size: 0.95rem;
            opacity: 0.9;
        }
        .content-grid {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
        }
        .article-content {
            background: white;
            padding: 40px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .article-content h2 {
            color: var(--primary);
            margin: 40px 0 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--secondary);
        }
        .article-content h3 {
            color: var(--dark);
            margin: 30px 0 15px;
        }
        .article-content p {
            margin-bottom: 20px;
            text-align: justify;
        }
        .article-content ul, .article-content ol {
            margin-bottom: 20px;
            padding-left: 30px;
        }
        .article-content li {
            margin-bottom: 10px;
        }
        .highlight {
            background: #fef3c7;
            padding: 20px;
            border-left: 4px solid var(--secondary);
            margin: 25px 0;
            border-radius: 0 var(--radius) var(--radius) 0;
        }
        .tip-box {
            background: #dbeafe;
            border: 1px solid var(--primary);
            padding: 20px;
            border-radius: var(--radius);
            margin: 25px 0;
        }
        .figure {
            margin: 30px auto;
            text-align: center;
        }
        .figure img {
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            margin-bottom: 10px;
        }
        .figcaption {
            font-style: italic;
            color: var(--gray);
            font-size: 0.9rem;
        }
        .interaction-section {
            background: white;
            padding: 30px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            margin-top: 40px;
        }
        .interaction-title {
            text-align: center;
            margin-bottom: 30px;
            color: var(--primary);
        }
        .interaction-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
        }
        .comment-form, .rating-form {
            display: flex;
            flex-direction: column;
            gap: 15px;
        }
        .form-group {
            display: flex;
            flex-direction: column;
            gap: 5px;
        }
        .form-label {
            font-weight: 600;
        }
        .form-input, .form-textarea {
            padding: 12px;
            border: 1px solid #d1d5db;
            border-radius: var(--radius);
            font-family: inherit;
            font-size: 1rem;
            resize: vertical;
        }
        .form-input:focus, .form-textarea:focus {
            outline: none;
            border-color: var(--primary);
        }
        .stars {
            display: flex;
            gap: 5px;
            font-size: 1.8rem;
            color: #d1d5db;
            cursor: pointer;
        }
        .stars i:hover,
        .stars i.active {
            color: var(--secondary);
        }
        .btn {
            background: var(--primary);
            color: white;
            border: none;
            padding: 12px 24px;
            border-radius: var(--radius);
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            align-self: flex-start;
        }
        .btn:hover {
            background: #4338ca;
            transform: translateY(-2px);
        }
        .sidebar {
            display: flex;
            flex-direction: column;
            gap: 30px;
        }
        .sidebar-widget {
            background: white;
            padding: 25px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .widget-title {
            color: var(--primary);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 1px solid #e5e7eb;
        }
        .toc-list {
            list-style: none;
        }
        .toc-item {
            margin-bottom: 10px;
        }
        .toc-link {
            color: var(--gray);
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 8px 0;
        }
        .toc-link:hover {
            color: var(--primary);
        }
        .toc-link i {
            color: var(--accent);
        }
        .author-box {
            text-align: center;
        }
        .author-img {
            width: 100px;
            height: 100px;
            border-radius: 50%;
            object-fit: cover;
            margin: 0 auto 15px;
            border: 3px solid var(--primary);
        }
        .author-name {
            font-weight: 700;
            margin-bottom: 5px;
        }
        .author-bio {
            color: var(--gray);
            font-size: 0.9rem;
        }
        .tag-list {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
        }
        .tag {
            background: #e0e7ff;
            color: var(--primary);
            padding: 5px 12px;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 500;
        }
        .tag:hover {
            background: var(--primary);
            color: white;
        }
        .footer-links {
            background: var(--dark);
            padding: 50px 20px;
            margin-top: 60px;
        }
        .web-links {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 20px;
            margin-bottom: 40px;
        }
        .web-link {
            background: rgba(255, 255, 255, 0.05);
            padding: 15px;
            border-radius: var(--radius);
            transition: var(--transition);
        }
        .web-link:hover {
            background: rgba(255, 255, 255, 0.1);
            transform: translateY(-3px);
        }
        .web-link a {
            color: #d1d5db;
            display: block;
        }
        .web-link a:hover {
            color: white;
        }
        .footer-bottom {
            background: #111827;
            color: #9ca3af;
            padding: 30px 20px;
            text-align: center;
        }
        .copyright {
            margin-bottom: 15px;
        }
        .social-links {
            display: flex;
            justify-content: center;
            gap: 20px;
            font-size: 1.3rem;
            margin-top: 20px;
        }
        .social-links a:hover {
            color: var(--secondary);
        }
        @media (max-width: 992px) {
            .content-grid {
                grid-template-columns: 1fr;
            }
            .article-title {
                font-size: 2.2rem;
            }
        }
        @media (max-width: 768px) {
            .mobile-toggle {
                display: block;
            }
            .nav {
                display: none;
                position: absolute;
                top: 100%;
                left: 0;
                right: 0;
                background: var(--dark);
            }
            .nav.active {
                display: block;
            }
            .nav-list {
                flex-direction: column;
            }
            .search-form {
                display: none;
            }
            .article-content {
                padding: 25px;
            }
            .article-title {
                font-size: 1.8rem;
            }
            .header-top {
                flex-wrap: wrap;
            }
            .logo {
                font-size: 1.6rem;
            }
        }
        @media print {
            .header, .sidebar, .interaction-section, .footer-links, .footer-bottom {
                display: none;
            }
            .article-content {
                box-shadow: none;
                padding: 0;
            }
        }