* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        :root {
            --primary-color: #1a237e;
            --secondary-color: #ff9800;
            --accent-color: #4fc3f7;
            --dark-bg: #121212;
            --light-bg: #f5f5f5;
            --text-dark: #333;
            --text-light: #f0f0f0;
            --card-shadow: 0 6px 15px rgba(0, 0, 0, 0.1);
            --transition: all 0.3s ease;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            background-color: var(--light-bg);
            color: var(--text-dark);
            line-height: 1.7;
            overflow-x: hidden;
        }
        a {
            color: var(--primary-color);
            text-decoration: none;
            transition: var(--transition);
        }
        a:hover {
            color: var(--secondary-color);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        .section {
            padding: 60px 0;
        }
        .site-header {
            background: linear-gradient(135deg, var(--primary-color) 0%, #283593 100%);
            color: var(--text-light);
            padding: 15px 0;
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 4px 12px rgba(0,0,0,0.2);
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .logo {
            font-size: 2rem;
            font-weight: 800;
            color: var(--secondary-color);
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
        }
        .logo a {
            color: inherit;
        }
        .logo span {
            color: var(--accent-color);
        }
        .main-nav ul {
            display: flex;
            list-style: none;
        }
        .main-nav li {
            margin-left: 25px;
        }
        .main-nav a {
            color: var(--text-light);
            font-weight: 600;
            padding: 8px 12px;
            border-radius: 4px;
        }
        .main-nav a:hover, .main-nav a.active {
            background-color: rgba(255, 255, 255, 0.15);
            color: var(--secondary-color);
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            cursor: pointer;
            color: var(--text-light);
        }
        .breadcrumb {
            background-color: #e8eaf6;
            padding: 12px 0;
            font-size: 0.9rem;
        }
        .breadcrumb .container {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
        }
        .breadcrumb a {
            color: #555;
        }
        .breadcrumb a:hover {
            color: var(--primary-color);
        }
        .breadcrumb i {
            margin: 0 8px;
            color: #888;
        }
        .hero-section {
            background: linear-gradient(rgba(26, 35, 126, 0.85), rgba(26, 35, 126, 0.9)), url('https://images.unsplash.com/photo-1534423861386-85a16f5d13fd?ixlib=rb-4.0.3&auto=format&fit=crop&w=1200&q=80') center/cover no-repeat;
            color: var(--text-light);
            text-align: center;
            padding: 80px 0;
        }
        .hero-section h1 {
            font-size: 3.2rem;
            margin-bottom: 20px;
            text-shadow: 2px 2px 8px rgba(0,0,0,0.5);
        }
        .hero-section p {
            font-size: 1.3rem;
            max-width: 800px;
            margin: 0 auto 30px;
            opacity: 0.9;
        }
        .search-box {
            max-width: 600px;
            margin: 30px auto;
            background: rgba(255, 255, 255, 0.1);
            padding: 20px;
            border-radius: 12px;
            backdrop-filter: blur(5px);
        }
        .search-box h3 {
            margin-bottom: 15px;
            color: var(--secondary-color);
        }
        .search-form {
            display: flex;
        }
        .search-input {
            flex: 1;
            padding: 14px 20px;
            border: none;
            border-radius: 8px 0 0 8px;
            font-size: 1rem;
        }
        .search-btn {
            background-color: var(--secondary-color);
            color: white;
            border: none;
            padding: 0 25px;
            border-radius: 0 8px 8px 0;
            cursor: pointer;
            font-weight: 600;
            transition: var(--transition);
        }
        .search-btn:hover {
            background-color: #ff8a00;
        }
        .content-card {
            background-color: white;
            border-radius: 12px;
            padding: 30px;
            margin-bottom: 30px;
            box-shadow: var(--card-shadow);
            transition: var(--transition);
        }
        .content-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 12px 20px rgba(0, 0, 0, 0.15);
        }
        .content-card h2 {
            color: var(--primary-color);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 3px solid var(--accent-color);
        }
        .content-card h3 {
            color: #444;
            margin: 25px 0 15px;
        }
        .content-card p {
            margin-bottom: 18px;
            text-align: justify;
        }
        .highlight {
            background-color: #e3f2fd;
            border-left: 5px solid var(--accent-color);
            padding: 20px;
            margin: 25px 0;
            border-radius: 0 8px 8px 0;
        }
        .hero-tier {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 25px;
            margin-top: 25px;
        }
        .tier-item {
            background: #f8f9fa;
            border-radius: 10px;
            padding: 20px;
            border: 2px solid #e0e0e0;
        }
        .tier-item.s-tier {
            border-color: #ffd700;
            background-color: #fff9e6;
        }
        .tier-item.a-tier {
            border-color: #c0c0c0;
            background-color: #f8f9ff;
        }
        .tier-item h4 {
            display: flex;
            align-items: center;
            color: var(--primary-color);
        }
        .tier-item h4 i {
            margin-right: 10px;
            color: var(--secondary-color);
        }
        .article-img {
            margin: 30px auto;
            max-width: 900px;
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 8px 20px rgba(0,0,0,0.1);
        }
        .img-caption {
            text-align: center;
            font-style: italic;
            color: #666;
            padding: 10px;
            background-color: #f9f9f9;
        }
        .user-interaction {
            background-color: #f0f7ff;
            border-radius: 12px;
            padding: 30px;
            margin-top: 40px;
        }
        .interaction-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
        }
        .rating-box, .comment-box {
            background: white;
            padding: 25px;
            border-radius: 10px;
            box-shadow: var(--card-shadow);
        }
        .stars {
            color: #ffc107;
            font-size: 1.8rem;
            margin: 15px 0;
            cursor: pointer;
        }
        .stars i:hover {
            transform: scale(1.2);
        }
        .form-group {
            margin-bottom: 20px;
        }
        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
        }
        .form-control {
            width: 100%;
            padding: 12px 15px;
            border: 1px solid #ccc;
            border-radius: 6px;
            font-size: 1rem;
        }
        .submit-btn {
            background-color: var(--primary-color);
            color: white;
            border: none;
            padding: 14px 28px;
            border-radius: 6px;
            cursor: pointer;
            font-weight: 600;
            transition: var(--transition);
        }
        .submit-btn:hover {
            background-color: var(--secondary-color);
        }
        .footer-links {
            background-color: #2c387e;
            color: var(--text-light);
            padding: 40px 0;
        }
        .web-link {
            display: inline-block;
            margin: 8px 15px 8px 0;
            padding: 8px 16px;
            background-color: rgba(255, 255, 255, 0.1);
            border-radius: 6px;
            transition: var(--transition);
        }
        .web-link:hover {
            background-color: var(--secondary-color);
        }
        .web-link a {
            color: var(--text-light);
        }
        .site-footer {
            background-color: var(--dark-bg);
            color: #aaa;
            text-align: center;
            padding: 30px 0;
            font-size: 0.95rem;
        }
        .footer-container {
            display: flex;
            flex-direction: column;
            align-items: center;
        }
        .social-links {
            margin: 20px 0;
        }
        .social-links a {
            color: #aaa;
            font-size: 1.5rem;
            margin: 0 12px;
            transition: var(--transition);
        }
        .social-links a:hover {
            color: var(--accent-color);
        }
        .copyright {
            margin-top: 20px;
            border-top: 1px solid #444;
            padding-top: 20px;
            width: 100%;
        }
        @media (max-width: 992px) {
            .hero-section h1 {
                font-size: 2.6rem;
            }
            .hero-tier {
                grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            }
        }
        @media (max-width: 768px) {
            .hamburger {
                display: block;
            }
            .main-nav ul {
                display: none;
                position: absolute;
                top: 100%;
                left: 0;
                width: 100%;
                background-color: var(--primary-color);
                flex-direction: column;
                padding: 20px;
                box-shadow: 0 10px 15px rgba(0,0,0,0.2);
            }
            .main-nav.active ul {
                display: flex;
            }
            .main-nav li {
                margin: 10px 0;
            }
            .header-container {
                flex-wrap: wrap;
            }
            .hero-section h1 {
                font-size: 2.2rem;
            }
            .hero-section p {
                font-size: 1.1rem;
            }
            .search-form {
                flex-direction: column;
            }
            .search-input, .search-btn {
                width: 100%;
                border-radius: 8px;
                margin-bottom: 10px;
            }
            .interaction-grid {
                grid-template-columns: 1fr;
            }
        }
        @media (max-width: 480px) {
            .hero-section {
                padding: 50px 0;
            }
            .content-card {
                padding: 20px;
            }
            .hero-tier {
                grid-template-columns: 1fr;
            }
        }