* {
            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: #333;
            background: #f8f9fa;
            max-width: 100%;
            overflow-x: hidden;
        }
        h1, h2, h3, h4 {
            color: #1a365d;
            margin-bottom: 1rem;
            font-weight: 700;
            line-height: 1.3;
        }
        h1 {
            font-size: 2.8rem;
            background: linear-gradient(90deg, #1a365d, #2c5282);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            margin-top: 1.5rem;
        }
        h2 {
            font-size: 2.2rem;
            border-left: 5px solid #2c5282;
            padding-left: 1rem;
            margin-top: 3rem;
        }
        h3 {
            font-size: 1.8rem;
            color: #2d3748;
            margin-top: 2rem;
        }
        p {
            margin-bottom: 1.5rem;
            font-size: 1.1rem;
            text-align: justify;
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        header {
            background: linear-gradient(135deg, #1a365d 0%, #2c5282 100%);
            color: white;
            padding: 1rem 0;
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .logo {
            font-family: 'Arial Black', sans-serif;
            font-size: 2.2rem;
            font-weight: 900;
            text-decoration: none;
            color: white;
            letter-spacing: -1px;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .logo span {
            color: #63b3ed;
            text-shadow: 0 2px 4px rgba(0,0,0,0.3);
        }
        .desktop-nav {
            display: flex;
            gap: 2rem;
        }
        .desktop-nav a {
            color: white;
            text-decoration: none;
            font-weight: 600;
            font-size: 1.1rem;
            padding: 0.5rem 1rem;
            border-radius: 4px;
            transition: all 0.3s ease;
        }
        .desktop-nav a:hover {
            background: rgba(255,255,255,0.15);
            transform: translateY(-2px);
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            background: none;
            border: none;
            color: white;
            cursor: pointer;
            padding: 5px;
        }
        .mobile-nav {
            display: none;
            flex-direction: column;
            background: #2c5282;
            position: absolute;
            top: 100%;
            left: 0;
            width: 100%;
            padding: 1rem;
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
        }
        .mobile-nav.active {
            display: flex;
        }
        .mobile-nav a {
            color: white;
            text-decoration: none;
            padding: 1rem;
            border-bottom: 1px solid rgba(255,255,255,0.1);
            transition: background 0.3s;
        }
        .mobile-nav a:hover {
            background: rgba(255,255,255,0.1);
        }
        .breadcrumb {
            padding: 1rem 0;
            background: #edf2f7;
            font-size: 0.95rem;
        }
        .breadcrumb a {
            color: #2c5282;
            text-decoration: none;
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        .breadcrumb span {
            color: #718096;
        }
        main {
            background: white;
            border-radius: 10px;
            box-shadow: 0 5px 20px rgba(0,0,0,0.08);
            margin: 2rem auto;
            padding: 2.5rem;
            overflow: hidden;
        }
        .article-intro {
            font-size: 1.3rem;
            color: #2d3748;
            font-weight: 500;
            border-left: 4px solid #63b3ed;
            padding-left: 1.5rem;
            margin: 2rem 0;
            background: #f0f9ff;
            padding: 1.5rem;
            border-radius: 0 8px 8px 0;
        }
        .highlight-box {
            background: linear-gradient(135deg, #f0f9ff, #e6fffa);
            border-left: 5px solid #38b2ac;
            padding: 1.5rem;
            margin: 2rem 0;
            border-radius: 0 8px 8px 0;
        }
        .content-image {
            width: 100%;
            max-width: 800px;
            height: auto;
            border-radius: 10px;
            margin: 2rem auto;
            display: block;
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
            transition: transform 0.5s ease;
        }
        .content-image:hover {
            transform: scale(1.02);
        }
        .image-caption {
            text-align: center;
            font-style: italic;
            color: #718096;
            margin-top: 0.5rem;
            font-size: 0.95rem;
        }
        .link-box {
            display: inline-block;
            background: #ebf8ff;
            color: #2c5282;
            padding: 0.5rem 1rem;
            border-radius: 6px;
            text-decoration: none;
            margin: 0.3rem;
            border: 1px solid #bee3f8;
            transition: all 0.3s ease;
        }
        .link-box:hover {
            background: #bee3f8;
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        }
        .key-term {
            background: #fffacd;
            padding: 0.2rem 0.5rem;
            border-radius: 3px;
            font-weight: 600;
            color: #744210;
        }
        .stat-box {
            background: #f7fafc;
            border: 2px solid #e2e8f0;
            border-radius: 10px;
            padding: 1.5rem;
            margin: 2rem 0;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 1.5rem;
        }
        .stat-item {
            text-align: center;
            padding: 1rem;
        }
        .stat-number {
            font-size: 2.5rem;
            font-weight: 800;
            color: #2c5282;
            display: block;
        }
        .stat-label {
            color: #718096;
            font-size: 1rem;
        }
        .interactive-section {
            background: #f8f9fa;
            border-radius: 12px;
            padding: 2rem;
            margin: 3rem 0;
            border: 1px solid #e9ecef;
        }
        .search-box {
            display: flex;
            max-width: 600px;
            margin: 0 auto 2rem;
        }
        .search-input {
            flex: 1;
            padding: 1rem 1.5rem;
            border: 2px solid #63b3ed;
            border-radius: 8px 0 0 8px;
            font-size: 1rem;
            outline: none;
            transition: border-color 0.3s;
        }
        .search-input:focus {
            border-color: #2c5282;
        }
        .search-button {
            background: linear-gradient(135deg, #2c5282, #4c7cb8);
            color: white;
            border: none;
            padding: 0 1.8rem;
            border-radius: 0 8px 8px 0;
            cursor: pointer;
            font-weight: 600;
            transition: all 0.3s ease;
        }
        .search-button:hover {
            background: linear-gradient(135deg, #1a365d, #2c5282);
            transform: translateX(2px);
        }
        .rating-section {
            text-align: center;
            padding: 2rem;
            background: white;
            border-radius: 10px;
            margin: 2rem 0;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
        }
        .stars {
            display: flex;
            justify-content: center;
            gap: 0.5rem;
            margin: 1.5rem 0;
        }
        .star {
            font-size: 2.5rem;
            color: #e2e8f0;
            cursor: pointer;
            transition: color 0.2s;
        }
        .star:hover,
        .star.active {
            color: #f6ad55;
        }
        .comment-form {
            display: flex;
            flex-direction: column;
            gap: 1.2rem;
            max-width: 800px;
            margin: 0 auto;
        }
        .form-group {
            display: flex;
            flex-direction: column;
            gap: 0.5rem;
        }
        .form-input, .form-textarea {
            padding: 1rem;
            border: 2px solid #e2e8f0;
            border-radius: 8px;
            font-size: 1rem;
            font-family: inherit;
            transition: border-color 0.3s;
        }
        .form-input:focus, .form-textarea:focus {
            border-color: #63b3ed;
            outline: none;
            box-shadow: 0 0 0 3px rgba(99, 179, 237, 0.2);
        }
        .form-textarea {
            min-height: 150px;
            resize: vertical;
        }
        .submit-button {
            background: linear-gradient(135deg, #38a169, #48bb78);
            color: white;
            border: none;
            padding: 1.2rem 2rem;
            border-radius: 8px;
            font-size: 1.1rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            align-self: flex-start;
        }
        .submit-button:hover {
            background: linear-gradient(135deg, #2f855a, #38a169);
            transform: translateY(-2px);
            box-shadow: 0 7px 20px rgba(56, 161, 105, 0.3);
        }
        footer {
            background: #1a202c;
            color: #cbd5e0;
            padding: 3rem 0 1.5rem;
            margin-top: 4rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2rem;
            margin-bottom: 2rem;
        }
        .footer-section h4 {
            color: white;
            margin-bottom: 1.5rem;
            font-size: 1.3rem;
        }
        friend-link {
            display: block;
            margin-bottom: 0.8rem;
        }
        friend-link a {
            color: #a0aec0;
            text-decoration: none;
            transition: color 0.3s;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        friend-link a:hover {
            color: #63b3ed;
        }
        .copyright {
            text-align: center;
            padding-top: 2rem;
            border-top: 1px solid #2d3748;
            color: #a0aec0;
            font-size: 0.9rem;
        }
        @media (max-width: 992px) {
            h1 { font-size: 2.4rem; }
            h2 { font-size: 2rem; }
            .desktop-nav { display: none; }
            .hamburger { display: block; }
        }
        @media (max-width: 768px) {
            .container { padding: 0 15px; }
            main { padding: 1.5rem; margin: 1rem auto; }
            h1 { font-size: 2rem; }
            h2 { font-size: 1.7rem; }
            .stat-box { grid-template-columns: 1fr; }
            .search-box { flex-direction: column; }
            .search-input { border-radius: 8px; margin-bottom: 0.5rem; }
            .search-button { border-radius: 8px; padding: 1rem; }
        }
        @media (max-width: 480px) {
            h1 { font-size: 1.8rem; }
            .logo { font-size: 1.8rem; }
            .interactive-section { padding: 1.5rem; }
            .stars { gap: 0.3rem; }
            .star { font-size: 2rem; }
        }
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }
        .fade-in {
            animation: fadeIn 0.6s ease-out forwards;
        }
        .text-center { text-align: center; }
        .mb-3 { margin-bottom: 3rem; }
        .mt-3 { margin-top: 3rem; }
        .emoji { font-size: 1.2em; }