* { 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: #2c3e50;
            background: linear-gradient(135deg, #f5f7fa 0%, #e4e9f2 100%);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }
        a { color: #2980b9; text-decoration: none; transition: color 0.3s ease, border-bottom 0.3s ease; }
        a:hover { color: #1a5276; border-bottom: 2px solid #1a5276; }
        img { max-width: 100%; height: auto; display: block; }
        .container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 20px; }
        .site-header {
            background: linear-gradient(90deg, #1a237e, #283593);
            color: white;
            padding: 1.2rem 0;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .my-logo {
            font-family: 'Georgia', serif;
            font-size: 2.2rem;
            font-weight: bold;
            color: #fff;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
        }
        .my-logo span { color: #4fc3f7; }
        .main-nav ul {
            display: flex;
            list-style: none;
            gap: 2rem;
        }
        .main-nav a {
            color: #e3f2fd;
            font-weight: 600;
            padding: 0.5rem 0.8rem;
            border-radius: 4px;
        }
        .main-nav a:hover {
            background-color: rgba(255,255,255,0.15);
            border-bottom: none;
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            background: none;
            border: none;
            color: white;
            cursor: pointer;
        }
        @media (max-width: 768px) {
            .hamburger { display: block; }
            .main-nav ul {
                flex-direction: column;
                position: absolute;
                top: 100%;
                left: 0;
                width: 100%;
                background: #283593;
                padding: 1rem;
                clip-path: polygon(0 0, 100% 0, 100% 0, 0 0);
                transition: clip-path 0.4s ease-in-out;
            }
            .main-nav.active ul {
                clip-path: polygon(0 0, 100% 0, 100% 100%, 0% 100%);
            }
        }
        .breadcrumb {
            padding: 1rem 0;
            background-color: #f1f8ff;
            font-size: 0.9rem;
        }
        .breadcrumb ol {
            display: flex;
            list-style: none;
            flex-wrap: wrap;
        }
        .breadcrumb li:not(:last-child)::after {
            content: '›';
            margin: 0 10px;
            color: #7f8c8d;
        }
        .breadcrumb a { color: #3498db; }
        main {
            flex: 1;
            padding: 2.5rem 0;
        }
        .article-header {
            text-align: center;
            margin-bottom: 3rem;
            padding-bottom: 2rem;
            border-bottom: 3px solid #dfe6e9;
        }
        h1 {
            font-size: 3rem;
            color: #1a237e;
            margin-bottom: 1rem;
            line-height: 1.2;
        }
        .article-meta {
            color: #7f8c8d;
            font-size: 0.95rem;
            display: flex;
            justify-content: center;
            align-items: center;
            gap: 1.5rem;
            flex-wrap: wrap;
        }
        .last-updated {
            background-color: #e8f4fc;
            padding: 0.4rem 0.8rem;
            border-radius: 20px;
            font-weight: 600;
        }
        .article-content {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 3rem;
        }
        @media (max-width: 992px) {
            .article-content { grid-template-columns: 1fr; }
        }
        .content-main {
            font-size: 1.1rem;
            background: white;
            padding: 2.5rem;
            border-radius: 12px;
            box-shadow: 0 6px 20px rgba(0,0,0,0.08);
        }
        h2, h3, h4 {
            color: #2c3e50;
            margin-top: 2.5rem;
            margin-bottom: 1rem;
            line-height: 1.3;
        }
        h2 { font-size: 2.2rem; border-left: 5px solid #3498db; padding-left: 15px; }
        h3 { font-size: 1.8rem; color: #2980b9; }
        h4 { font-size: 1.5rem; color: #16a085; }
        p {
            margin-bottom: 1.5rem;
            text-align: justify;
        }
        .intro {
            font-size: 1.25rem;
            font-weight: 500;
            color: #2d3436;
            background-color: #f9f9f9;
            padding: 1.5rem;
            border-left: 4px solid #e74c3c;
            margin-bottom: 2.5rem;
            border-radius: 0 8px 8px 0;
        }
        .highlight {
            background-color: #fffde7;
            padding: 1.5rem;
            border-radius: 8px;
            border: 1px solid #ffeb3b;
            margin: 2rem 0;
        }
        .highlight strong { color: #e67e22; }
        .image-container {
            margin: 2.5rem auto;
            text-align: center;
            max-width: 800px;
        }
        .image-container img {
            border-radius: 10px;
            box-shadow: 0 10px 25px rgba(0,0,0,0.15);
            border: 1px solid #ddd;
        }
        .image-caption {
            font-style: italic;
            color: #666;
            margin-top: 0.8rem;
            font-size: 0.95rem;
        }
        blockquote {
            font-style: italic;
            color: #555;
            border-left: 4px solid #9b59b6;
            padding-left: 1.5rem;
            margin: 2rem 0;
            background-color: #f8f9fa;
            padding: 1.5rem;
            border-radius: 0 8px 8px 0;
        }
        .sidebar {
            background: white;
            padding: 2rem;
            border-radius: 12px;
            box-shadow: 0 6px 20px rgba(0,0,0,0.08);
            align-self: start;
            position: sticky;
            top: 140px;
        }
        .sidebar-widget {
            margin-bottom: 2.5rem;
        }
        .sidebar h3 {
            font-size: 1.5rem;
            color: #2c3e50;
            margin-bottom: 1.2rem;
            padding-bottom: 0.5rem;
            border-bottom: 2px solid #ecf0f1;
        }
        .search-form {
            display: flex;
        }
        .search-form input {
            flex: 1;
            padding: 0.9rem;
            border: 2px solid #bdc3c7;
            border-right: none;
            border-radius: 6px 0 0 6px;
            font-size: 1rem;
        }
        .search-form button {
            background: #3498db;
            color: white;
            border: none;
            padding: 0 1.5rem;
            border-radius: 0 6px 6px 0;
            cursor: pointer;
            transition: background 0.3s;
        }
        .search-form button:hover { background: #2980b9; }
        .rating-widget .stars {
            display: flex;
            gap: 5px;
            margin-bottom: 1rem;
        }
        .stars input { display: none; }
        .stars label {
            font-size: 1.8rem;
            color: #ddd;
            cursor: pointer;
            transition: color 0.2s;
        }
        .stars input:checked ~ label,
        .stars label:hover,
        .stars label:hover ~ label { color: #f1c40f; }
        .comment-form textarea,
        .comment-form input {
            width: 100%;
            padding: 0.8rem;
            margin-bottom: 1rem;
            border: 1px solid #bdc3c7;
            border-radius: 6px;
            font-family: inherit;
        }
        .comment-form button,
        .rating-widget button {
            width: 100%;
            padding: 0.9rem;
            background: linear-gradient(to right, #27ae60, #2ecc71);
            color: white;
            border: none;
            border-radius: 6px;
            font-weight: bold;
            cursor: pointer;
            transition: opacity 0.3s;
        }
        .comment-form button:hover,
        .rating-widget button:hover { opacity: 0.9; }
        .site-footer {
            background: #2c3e50;
            color: #ecf0f1;
            padding: 3rem 0 1.5rem;
            margin-top: 3rem;
        }
        .footer-container {
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            gap: 2rem;
        }
        .footer-section {
            flex: 1;
            min-width: 250px;
        }
        .footer-section h3 {
            color: #3498db;
            margin-bottom: 1.5rem;
            font-size: 1.4rem;
        }
        .footer-links {
            list-style: none;
        }
        .footer-links li { margin-bottom: 0.8rem; }
        .footer-links a {
            color: #bdc3c7;
            text-decoration: none;
        }
        .footer-links a:hover { color: #3498db; border-bottom: none; }
        friend-link {
            display: block;
            background: #34495e;
            padding: 1rem;
            border-radius: 6px;
            margin-bottom: 1rem;
            border-left: 4px solid #3498db;
        }
        .copyright {
            text-align: center;
            margin-top: 3rem;
            padding-top: 1.5rem;
            border-top: 1px solid #4a6572;
            color: #95a5a6;
            font-size: 0.9rem;
        }
        .btn {
            display: inline-block;
            padding: 0.7rem 1.5rem;
            background: #3498db;
            color: white;
            border-radius: 6px;
            font-weight: 600;
            border: none;
            cursor: pointer;
            transition: all 0.3s;
        }
        .btn:hover {
            background: #2980b9;
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        }
        .text-center { text-align: center; }
        .mt-3 { margin-top: 3rem; }
        .mb-3 { margin-bottom: 3rem; }