* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        :root {
            --primary-color: #4CAF50;
            --secondary-color: #FF9800;
            --accent-color: #2196F3;
            --dark-color: #2C3E50;
            --light-color: #F5F7FA;
            --text-color: #333333;
            --text-light: #666666;
            --shadow: 0 4px 12px rgba(0,0,0,0.1);
            --radius: 8px;
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.7;
            color: var(--text-color);
            background-color: var(--light-color);
            overflow-x: hidden;
        }
        .site-header {
            background-color: white;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .logo {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary-color);
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .logo i {
            color: var(--secondary-color);
        }
        .nav-desktop {
            display: flex;
            gap: 30px;
        }
        @media (max-width: 768px) {
            .nav-desktop {
                display: none;
            }
        }
        .nav-link {
            text-decoration: none;
            color: var(--dark-color);
            font-weight: 600;
            padding: 10px 0;
            position: relative;
            transition: var(--transition);
        }
        .nav-link:hover {
            color: var(--primary-color);
        }
        .nav-link::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 2px;
            background-color: var(--primary-color);
            transition: var(--transition);
        }
        .nav-link:hover::after {
            width: 100%;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            font-size: 1.5rem;
            color: var(--dark-color);
            cursor: pointer;
        }
        @media (max-width: 768px) {
            .hamburger {
                display: block;
            }
        }
        .mobile-nav {
            display: none;
            flex-direction: column;
            background-color: white;
            padding: 20px;
            box-shadow: var(--shadow);
            position: absolute;
            top: 100%;
            left: 0;
            width: 100%;
            z-index: 999;
        }
        .mobile-nav.active {
            display: flex;
        }
        .mobile-nav .nav-link {
            padding: 15px 0;
            border-bottom: 1px solid #eee;
        }
        .breadcrumb {
            background-color: #f8f9fa;
            padding: 15px 20px;
            max-width: 1200px;
            margin: 0 auto;
        }
        .breadcrumb-list {
            display: flex;
            list-style: none;
            flex-wrap: wrap;
            gap: 10px;
        }
        .breadcrumb-item {
            color: var(--text-light);
            font-size: 0.9rem;
        }
        .breadcrumb-item a {
            color: var(--accent-color);
            text-decoration: none;
        }
        .breadcrumb-item a:hover {
            text-decoration: underline;
        }
        .breadcrumb-item::after {
            content: '>';
            margin-left: 10px;
        }
        .breadcrumb-item:last-child::after {
            content: '';
        }
        .main-container {
            max-width: 1200px;
            margin: 30px auto;
            padding: 0 20px;
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
        }
        @media (max-width: 992px) {
            .main-container {
                grid-template-columns: 1fr;
            }
        }
        .article-content {
            background-color: white;
            padding: 40px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .article-title {
            font-size: 2.2rem;
            color: var(--dark-color);
            margin-bottom: 20px;
            line-height: 1.3;
        }
        .article-meta {
            display: flex;
            gap: 20px;
            color: var(--text-light);
            margin-bottom: 30px;
            font-size: 0.9rem;
        }
        .meta-item {
            display: flex;
            align-items: center;
            gap: 5px;
        }
        .content-section {
            margin-bottom: 40px;
        }
        .section-title {
            font-size: 1.8rem;
            color: var(--primary-color);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid #eee;
        }
        .subsection-title {
            font-size: 1.4rem;
            color: var(--dark-color);
            margin: 25px 0 15px;
        }
        .highlight-box {
            background-color: #E8F5E9;
            border-left: 4px solid var(--primary-color);
            padding: 20px;
            margin: 25px 0;
            border-radius: 0 var(--radius) var(--radius) 0;
        }
        .feature-list {
            list-style: none;
            margin: 20px 0;
        }
        .feature-list li {
            padding: 10px 0;
            padding-left: 30px;
            position: relative;
        }
        .feature-list li::before {
            content: '✓';
            position: absolute;
            left: 0;
            color: var(--primary-color);
            font-weight: bold;
        }
        .article-image {
            width: 100%;
            height: auto;
            border-radius: var(--radius);
            margin: 25px 0;
            box-shadow: var(--shadow);
            transition: var(--transition);
        }
        .article-image:hover {
            transform: scale(1.01);
        }
        .interactive-section {
            background-color: #f8f9fa;
            padding: 30px;
            border-radius: var(--radius);
            margin: 40px 0;
        }
        .form-group {
            margin-bottom: 20px;
        }
        .form-label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
        }
        .form-input, .form-textarea {
            width: 100%;
            padding: 12px 15px;
            border: 1px solid #ddd;
            border-radius: var(--radius);
            font-family: inherit;
            font-size: 1rem;
            transition: var(--transition);
        }
        .form-input:focus, .form-textarea:focus {
            outline: none;
            border-color: var(--accent-color);
            box-shadow: 0 0 0 3px rgba(33, 150, 243, 0.1);
        }
        .form-textarea {
            min-height: 150px;
            resize: vertical;
        }
        .btn {
            background-color: var(--primary-color);
            color: white;
            border: none;
            padding: 12px 25px;
            border-radius: var(--radius);
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            display: inline-flex;
            align-items: center;
            gap: 8px;
        }
        .btn:hover {
            background-color: #3d8b40;
            transform: translateY(-2px);
        }
        .btn-secondary {
            background-color: var(--secondary-color);
        }
        .btn-secondary:hover {
            background-color: #e68900;
        }
        .rating-system {
            display: flex;
            align-items: center;
            gap: 15px;
            margin: 20px 0;
        }
        .star-rating {
            display: flex;
            gap: 5px;
        }
        .star {
            color: #ddd;
            font-size: 1.5rem;
            cursor: pointer;
            transition: var(--transition);
        }
        .star:hover, .star.active {
            color: #FFD700;
        }
        .sidebar {
            display: flex;
            flex-direction: column;
            gap: 30px;
        }
        .sidebar-widget {
            background-color: white;
            padding: 25px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .widget-title {
            font-size: 1.3rem;
            color: var(--dark-color);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid #eee;
        }
        .download-box {
            background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
            color: white;
            text-align: center;
            padding: 30px;
            border-radius: var(--radius);
        }
        .download-btn {
            background-color: white;
            color: var(--primary-color);
            margin-top: 20px;
            font-size: 1.1rem;
            padding: 15px 30px;
        }
        .download-btn:hover {
            background-color: #f0f0f0;
        }
        .footer-links {
            max-width: 1200px;
            margin: 40px auto 0;
            padding: 0 20px;
        }
        .web-link {
            background-color: white;
            margin-bottom: 15px;
            padding: 15px 20px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .web-link a {
            color: var(--accent-color);
            text-decoration: none;
            font-weight: 600;
            transition: var(--transition);
        }
        .web-link a:hover {
            color: var(--primary-color);
            text-decoration: underline;
        }
        .site-footer {
            background-color: var(--dark-color);
            color: white;
            padding: 40px 20px;
            margin-top: 50px;
        }
        .footer-container {
            max-width: 1200px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 40px;
        }
        .footer-section h3 {
            font-size: 1.3rem;
            margin-bottom: 20px;
            color: var(--light-color);
        }
        .footer-links-list {
            list-style: none;
        }
        .footer-links-list li {
            margin-bottom: 10px;
        }
        .footer-links-list a {
            color: #ccc;
            text-decoration: none;
            transition: var(--transition);
        }
        .footer-links-list a:hover {
            color: white;
            padding-left: 5px;
        }
        .copyright {
            text-align: center;
            padding-top: 30px;
            margin-top: 30px;
            border-top: 1px solid #444;
            color: #aaa;
            font-size: 0.9rem;
        }
        @media (max-width: 768px) {
            .article-content {
                padding: 25px;
            }
            .article-title {
                font-size: 1.8rem;
            }
            .section-title {
                font-size: 1.5rem;
            }
            .interactive-section {
                padding: 20px;
            }
            .main-container {
                gap: 30px;
            }
        }
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }
        .fade-in {
            animation: fadeIn 0.6s ease-out;
        }
        @media print {
            .site-header, .sidebar, .interactive-section, .site-footer {
                display: none;
            }
            .article-content {
                box-shadow: none;
                padding: 0;
            }
        }