:root {
            --primary-color: #1e40af;
            --secondary-color: #dc2626;
            --accent-color: #fbbf24;
            --text-dark: #1f2937;
            --text-light: #6b7280;
            --bg-light: #f9fafb;
            --bg-white: #ffffff;
            --border-color: #e5e7eb;
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.12);
            --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
            --shadow-lg: 0 10px 25px rgba(0,0,0,0.15);
            --transition: all 0.3s ease;
            --radius: 8px;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.7;
            color: var(--text-dark);
            background-color: var(--bg-light);
            overflow-x: hidden;
        }
        a {
            text-decoration: none;
            color: inherit;
            transition: var(--transition);
        }
        ul, ol {
            list-style-position: inside;
            margin-left: 1rem;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        .btn {
            display: inline-block;
            padding: 12px 28px;
            background-color: var(--primary-color);
            color: white;
            border-radius: var(--radius);
            font-weight: 600;
            border: none;
            cursor: pointer;
            transition: var(--transition);
            text-align: center;
        }
        .btn:hover {
            background-color: #1e3a8a;
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }
        .btn-secondary {
            background-color: var(--secondary-color);
        }
        .btn-secondary:hover {
            background-color: #b91c1c;
        }
        .site-header {
            background-color: var(--bg-white);
            box-shadow: var(--shadow-sm);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 15px 0;
            border-bottom: 1px solid var(--border-color);
        }
        .my-logo {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--primary-color);
            background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            letter-spacing: -1px;
        }
        .my-logo:hover {
            opacity: 0.9;
        }
        .search-box {
            display: flex;
            max-width: 400px;
            width: 100%;
        }
        .search-input {
            flex: 1;
            padding: 12px 16px;
            border: 2px solid var(--border-color);
            border-radius: var(--radius) 0 0 var(--radius);
            font-size: 1rem;
            outline: none;
        }
        .search-input:focus {
            border-color: var(--primary-color);
        }
        .search-btn {
            background-color: var(--primary-color);
            color: white;
            border: none;
            padding: 0 22px;
            border-radius: 0 var(--radius) var(--radius) 0;
            cursor: pointer;
            transition: var(--transition);
        }
        .search-btn:hover {
            background-color: #1e3a8a;
        }
        .nav-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 10px 0;
        }
        .main-nav ul {
            display: flex;
            gap: 30px;
        }
        .main-nav a {
            font-weight: 600;
            font-size: 1.05rem;
            color: var(--text-dark);
            padding: 8px 0;
            position: relative;
        }
        .main-nav a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 3px;
            background-color: var(--secondary-color);
            transition: var(--transition);
        }
        .main-nav a:hover {
            color: var(--secondary-color);
        }
        .main-nav a:hover::after {
            width: 100%;
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            cursor: pointer;
            color: var(--primary-color);
        }
        .breadcrumb {
            padding: 15px 0;
            background-color: #f1f5f9;
            font-size: 0.9rem;
            color: var(--text-light);
            margin-bottom: 30px;
        }
        .breadcrumb a {
            color: var(--primary-color);
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        .main-content {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
            padding: 30px 0;
        }
        .article-content {
            background-color: var(--bg-white);
            padding: 40px;
            border-radius: var(--radius);
            box-shadow: var(--shadow-sm);
        }
        .sidebar {
            background-color: var(--bg-white);
            padding: 25px;
            border-radius: var(--radius);
            box-shadow: var(--shadow-sm);
            align-self: start;
            position: sticky;
            top: 120px;
        }
        .article-header {
            margin-bottom: 30px;
            border-bottom: 2px solid var(--border-color);
            padding-bottom: 20px;
        }
        .article-header h1 {
            font-size: 2.8rem;
            line-height: 1.2;
            margin-bottom: 15px;
            color: var(--text-dark);
        }
        .meta-info {
            display: flex;
            align-items: center;
            gap: 20px;
            color: var(--text-light);
            font-size: 0.95rem;
            flex-wrap: wrap;
        }
        .meta-info i {
            margin-right: 6px;
        }
        .highlight {
            background-color: #fef3c7;
            padding: 25px;
            border-radius: var(--radius);
            border-left: 5px solid var(--accent-color);
            margin: 30px 0;
        }
        .feature-img {
            margin: 30px 0;
            border-radius: var(--radius);
            overflow: hidden;
            box-shadow: var(--shadow-lg);
        }
        .feature-img figcaption {
            text-align: center;
            font-style: italic;
            padding: 10px;
            color: var(--text-light);
            font-size: 0.9rem;
        }
        .content-section {
            margin-bottom: 40px;
        }
        .content-section h2 {
            font-size: 2rem;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--border-color);
            color: var(--primary-color);
        }
        .content-section h3 {
            font-size: 1.6rem;
            margin: 25px 0 15px;
            color: var(--text-dark);
        }
        .content-section h4 {
            font-size: 1.3rem;
            margin: 20px 0 12px;
            color: var(--secondary-color);
        }
        .content-section p {
            margin-bottom: 18px;
            text-align: justify;
        }
        .content-section ul, .content-section ol {
            margin-bottom: 20px;
            padding-left: 25px;
        }
        .content-section li {
            margin-bottom: 10px;
        }
        .internal-link {
            color: var(--primary-color);
            font-weight: 600;
            border-bottom: 1px dotted var(--primary-color);
        }
        .internal-link:hover {
            color: var(--secondary-color);
            border-bottom-style: solid;
        }
        .tip-box {
            background-color: #dbeafe;
            padding: 20px;
            border-radius: var(--radius);
            margin: 25px 0;
            border-left: 5px solid var(--primary-color);
        }
        .tip-box strong {
            color: var(--primary-color);
        }
        .interactive-section {
            background-color: var(--bg-light);
            padding: 30px;
            border-radius: var(--radius);
            margin: 40px 0;
            border: 1px solid var(--border-color);
        }
        .rating-section, .comment-section {
            margin-bottom: 40px;
        }
        .rating-title, .comment-title {
            font-size: 1.5rem;
            margin-bottom: 20px;
            color: var(--primary-color);
        }
        .star-rating {
            display: flex;
            gap: 10px;
            margin-bottom: 20px;
        }
        .star-rating .star {
            font-size: 2rem;
            color: #d1d5db;
            cursor: pointer;
            transition: var(--transition);
        }
        .star-rating .star:hover,
        .star-rating .star.active {
            color: var(--accent-color);
        }
        .rating-form, .comment-form {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }
        .form-group {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        .form-group label {
            font-weight: 600;
            color: var(--text-dark);
        }
        .form-control {
            padding: 14px;
            border: 2px solid var(--border-color);
            border-radius: var(--radius);
            font-size: 1rem;
            font-family: inherit;
            transition: var(--transition);
        }
        .form-control:focus {
            border-color: var(--primary-color);
            outline: none;
            box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.1);
        }
        textarea.form-control {
            min-height: 150px;
            resize: vertical;
        }
        .sidebar h3 {
            font-size: 1.4rem;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--border-color);
            color: var(--primary-color);
        }
        .related-links {
            margin-bottom: 30px;
        }
        .related-links ul {
            list-style: none;
            padding-left: 0;
        }
        .related-links li {
            margin-bottom: 12px;
            padding-bottom: 12px;
            border-bottom: 1px dashed var(--border-color);
        }
        .related-links a {
            display: block;
            padding: 10px;
            border-radius: 6px;
            transition: var(--transition);
        }
        .related-links a:hover {
            background-color: #eff6ff;
            padding-left: 15px;
            color: var(--primary-color);
        }
        .sidebar-cta {
            background: linear-gradient(135deg, var(--primary-color), #4338ca);
            color: white;
            padding: 25px;
            border-radius: var(--radius);
            text-align: center;
        }
        .sidebar-cta h3 {
            color: white;
            border-bottom: none;
            margin-bottom: 15px;
        }
        .site-footer {
            background-color: #111827;
            color: #d1d5db;
            padding: 50px 0 20px;
            margin-top: 60px;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 40px;
            margin-bottom: 40px;
        }
        .footer-logo {
            font-size: 2.2rem;
            font-weight: 800;
            color: white;
            margin-bottom: 15px;
        }
        .footer-links h4 {
            color: white;
            font-size: 1.3rem;
            margin-bottom: 20px;
            position: relative;
            padding-bottom: 10px;
        }
        .footer-links h4::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 40px;
            height: 3px;
            background-color: var(--secondary-color);
        }
        .footer-links ul {
            list-style: none;
            padding-left: 0;
        }
        .footer-links li {
            margin-bottom: 12px;
        }
        .footer-links a {
            color: #9ca3af;
            transition: var(--transition);
        }
        .footer-links a:hover {
            color: white;
            padding-left: 5px;
        }
        friend-link {
            display: block;
            background-color: #1f2937;
            padding: 20px;
            border-radius: var(--radius);
            margin-bottom: 20px;
        }
        friend-link a {
            color: var(--accent-color);
            font-weight: 600;
        }
        friend-link a:hover {
            text-decoration: underline;
        }
        .copyright {
            text-align: center;
            padding-top: 25px;
            border-top: 1px solid #374151;
            color: #9ca3af;
            font-size: 0.9rem;
        }
        @media (max-width: 992px) {
            .main-content {
                grid-template-columns: 1fr;
            }
            .sidebar {
                position: static;
            }
            .article-header h1 {
                font-size: 2.3rem;
            }
        }
        @media (max-width: 768px) {
            .header-top {
                flex-direction: column;
                gap: 20px;
                padding: 20px 0;
            }
            .search-box {
                max-width: 100%;
            }
            .hamburger {
                display: block;
            }
            .main-nav ul {
                display: none;
                flex-direction: column;
                position: absolute;
                top: 100%;
                left: 0;
                width: 100%;
                background-color: var(--bg-white);
                box-shadow: var(--shadow-md);
                padding: 20px;
                z-index: 999;
            }
            .main-nav.active ul {
                display: flex;
            }
            .nav-container {
                flex-wrap: wrap;
            }
            .article-content {
                padding: 25px;
            }
            .article-header h1 {
                font-size: 2rem;
            }
            .content-section h2 {
                font-size: 1.7rem;
            }
            .content-section h3 {
                font-size: 1.4rem;
            }
            .footer-content {
                grid-template-columns: 1fr;
                gap: 30px;
            }
        }
        @media (max-width: 480px) {
            .article-header h1 {
                font-size: 1.7rem;
            }
            .meta-info {
                flex-direction: column;
                align-items: flex-start;
                gap: 10px;
            }
            .btn {
                padding: 10px 20px;
                width: 100%;
            }
            .interactive-section {
                padding: 20px;
            }
        }