:root {
            --primary: #2563eb;
            --secondary: #1e40af;
            --accent: #f59e0b;
            --light: #f8fafc;
            --dark: #1e293b;
            --gray: #64748b;
            --success: #10b981;
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
            --radius: 8px;
            --transition: all 0.3s ease;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', 'Nirmala UI', sans-serif;
        }
        body {
            background-color: #f1f5f9;
            color: #334155;
            line-height: 1.7;
            overflow-x: hidden;
        }
        header {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            color: white;
            padding: 1rem 0;
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
        }
        .header-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 1.5rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .logo a {
            font-size: 1.8rem;
            font-weight: 800;
            color: white;
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .logo i {
            color: var(--accent);
        }
        nav {
            display: flex;
            align-items: center;
            gap: 2rem;
        }
        .nav-links {
            display: flex;
            gap: 2rem;
            list-style: none;
        }
        .nav-links a {
            color: white;
            text-decoration: none;
            font-weight: 600;
            font-size: 1rem;
            transition: var(--transition);
            padding: 0.5rem 0;
            position: relative;
        }
        .nav-links a:hover {
            color: var(--accent);
        }
        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--accent);
            transition: width 0.3s ease;
        }
        .nav-links a:hover::after {
            width: 100%;
        }
        .search-form {
            display: flex;
            align-items: center;
            background: rgba(255, 255, 255, 0.15);
            border-radius: 50px;
            padding: 0.3rem 0.8rem;
        }
        .search-form input {
            background: transparent;
            border: none;
            color: white;
            padding: 0.5rem;
            width: 200px;
            outline: none;
        }
        .search-form input::placeholder {
            color: rgba(255, 255, 255, 0.7);
        }
        .search-form button {
            background: transparent;
            border: none;
            color: white;
            cursor: pointer;
            font-size: 1.1rem;
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.5rem;
            cursor: pointer;
        }
        .breadcrumb {
            max-width: 1200px;
            margin: 1.5rem auto;
            padding: 0 1.5rem;
            font-size: 0.9rem;
        }
        .breadcrumb a {
            color: var(--primary);
            text-decoration: none;
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        main {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 1.5rem 3rem;
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 2.5rem;
        }
        .article-content {
            background: white;
            border-radius: var(--radius);
            padding: 2.5rem;
            box-shadow: var(--shadow);
        }
        h1 {
            color: var(--dark);
            font-size: 2.5rem;
            margin-bottom: 1.5rem;
            line-height: 1.3;
        }
        h2 {
            color: var(--primary);
            font-size: 1.8rem;
            margin: 2.5rem 0 1.2rem;
            padding-bottom: 0.5rem;
            border-bottom: 2px solid #e2e8f0;
        }
        h3 {
            color: var(--secondary);
            font-size: 1.4rem;
            margin: 1.8rem 0 1rem;
        }
        p {
            margin-bottom: 1.5rem;
            text-align: justify;
            font-size: 1.1rem;
        }
        .lead {
            font-size: 1.2rem;
            color: var(--dark);
            font-weight: 600;
            background: #f0f9ff;
            padding: 1.2rem;
            border-radius: var(--radius);
            border-left: 4px solid var(--primary);
            margin-bottom: 2rem;
        }
        .highlight {
            background: linear-gradient(120deg, #fef3c7 0%, #fef3c7 100%);
            padding: 1.5rem;
            border-radius: var(--radius);
            border: 1px solid #fbbf24;
            margin: 2rem 0;
        }
        .feature-list {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 1.5rem;
            margin: 2rem 0;
        }
        .feature-card {
            background: #f8fafc;
            border-radius: var(--radius);
            padding: 1.5rem;
            border-top: 4px solid var(--primary);
            transition: var(--transition);
        }
        .feature-card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow);
        }
        .feature-card i {
            color: var(--primary);
            font-size: 2rem;
            margin-bottom: 1rem;
        }
        .image-container {
            margin: 2.5rem 0;
            text-align: center;
        }
        .article-image {
            width: 100%;
            max-width: 800px;
            height: auto;
            border-radius: var(--radius);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.12);
            transition: transform 0.5s ease;
        }
        .article-image:hover {
            transform: scale(1.02);
        }
        .download-box {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            color: white;
            padding: 2rem;
            border-radius: var(--radius);
            text-align: center;
            margin: 2.5rem 0;
            position: relative;
            overflow: hidden;
        }
        .download-box::before {
            content: "";
            position: absolute;
            top: -50%;
            left: -50%;
            width: 200%;
            height: 200%;
            background: radial-gradient(circle, rgba(255,255,255,0.1) 1%, transparent 1%);
            background-size: 20px 20px;
            opacity: 0.3;
            animation: float 20s linear infinite;
        }
        @keyframes float {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }
        .download-btn {
            display: inline-block;
            background: var(--accent);
            color: var(--dark);
            padding: 1rem 2.5rem;
            font-size: 1.2rem;
            font-weight: 700;
            border-radius: 50px;
            text-decoration: none;
            margin-top: 1.5rem;
            transition: var(--transition);
            box-shadow: 0 4px 15px rgba(245, 158, 11, 0.4);
        }
        .download-btn:hover {
            background: #fbbf24;
            transform: translateY(-3px);
            box-shadow: 0 6px 20px rgba(245, 158, 11, 0.6);
        }
        aside {
            display: flex;
            flex-direction: column;
            gap: 2rem;
        }
        .sidebar-widget {
            background: white;
            border-radius: var(--radius);
            padding: 1.8rem;
            box-shadow: var(--shadow);
        }
        .widget-title {
            color: var(--dark);
            font-size: 1.3rem;
            margin-bottom: 1.2rem;
            padding-bottom: 0.7rem;
            border-bottom: 2px solid #e2e8f0;
        }
        .rating-widget {
            text-align: center;
        }
        .stars {
            color: #fbbf24;
            font-size: 1.8rem;
            margin: 1rem 0;
        }
        .rating-form input, .comment-form input, .comment-form textarea {
            width: 100%;
            padding: 0.8rem;
            margin-bottom: 1rem;
            border: 1px solid #cbd5e1;
            border-radius: var(--radius);
            font-size: 1rem;
        }
        .rating-form button, .comment-form button {
            width: 100%;
            padding: 0.9rem;
            background: var(--primary);
            color: white;
            border: none;
            border-radius: var(--radius);
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
        }
        .rating-form button:hover, .comment-form button:hover {
            background: var(--secondary);
        }
        .longtail-links {
            max-width: 1200px;
            margin: 2rem auto 0;
            padding: 2rem 1.5rem;
            background: white;
            border-radius: var(--radius) var(--radius) 0 0;
            box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.05);
        }
        .web-links-container {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            gap: 1rem;
        }
        .web-link {
            background: #f8fafc;
            padding: 0.9rem 1.2rem;
            border-radius: var(--radius);
            transition: var(--transition);
        }
        .web-link:hover {
            background: #e2e8f0;
            transform: translateX(5px);
        }
        .web-link a {
            color: var(--primary);
            text-decoration: none;
            font-weight: 500;
            display: block;
        }
        .web-link a:hover {
            text-decoration: underline;
        }
        footer {
            background: var(--dark);
            color: #cbd5e1;
            padding: 3rem 1.5rem;
            text-align: center;
        }
        .footer-container {
            max-width: 1200px;
            margin: 0 auto;
        }
        .copyright {
            margin-top: 2rem;
            padding-top: 1.5rem;
            border-top: 1px solid #475569;
            font-size: 0.95rem;
        }
        @media (max-width: 992px) {
            main {
                grid-template-columns: 1fr;
            }
            h1 {
                font-size: 2.2rem;
            }
            .feature-list {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 768px) {
            .hamburger {
                display: block;
            }
            .nav-links {
                position: fixed;
                top: 70px;
                left: -100%;
                width: 100%;
                height: calc(100vh - 70px);
                background: var(--primary);
                flex-direction: column;
                align-items: center;
                justify-content: flex-start;
                padding-top: 3rem;
                transition: left 0.4s ease;
                z-index: 999;
            }
            .nav-links.active {
                left: 0;
            }
            .search-form input {
                width: 150px;
            }
            .feature-list {
                grid-template-columns: 1fr;
            }
            .article-content {
                padding: 1.8rem;
            }
        }
        @media (max-width: 480px) {
            h1 {
                font-size: 1.9rem;
            }
            h2 {
                font-size: 1.5rem;
            }
            .download-box {
                padding: 1.5rem;
            }
            .download-btn {
                padding: 0.9rem 2rem;
                font-size: 1.1rem;
            }
        }
        @media print {
            header, aside, .longtail-links, footer, .download-box, .hamburger, .search-form {
                display: none;
            }
            main {
                grid-template-columns: 1fr;
                padding: 0;
            }
            .article-content {
                box-shadow: none;
                padding: 0;
            }
        }