* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        :root {
            --primary: #2c3e50;
            --secondary: #3498db;
            --accent: #e74c3c;
            --light: #ecf0f1;
            --dark: #2c3e50;
            --success: #27ae60;
            --warning: #f39c12;
            --shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
            --radius: 8px;
            --transition: all 0.3s ease;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            background-color: #f9f9f9;
            color: #333;
            line-height: 1.7;
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }
        a {
            text-decoration: none;
            color: var(--secondary);
            transition: var(--transition);
        }
        a:hover {
            color: var(--accent);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        header {
            background: var(--primary);
            color: white;
            padding: 1rem 0;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
        }
        .logo {
            font-size: 2.2rem;
            font-weight: 800;
            letter-spacing: -1px;
        }
        .logo a {
            color: white;
            display: flex;
            align-items: center;
        }
        .logo .fa-chess-board {
            color: var(--accent);
            margin-right: 10px;
            font-size: 2.5rem;
        }
        .logo span {
            color: var(--accent);
        }
        .search-form {
            flex-grow: 1;
            max-width: 500px;
            margin: 0 30px;
            position: relative;
        }
        .search-form input {
            width: 100%;
            padding: 12px 20px;
            padding-right: 50px;
            border: none;
            border-radius: 50px;
            background: rgba(255, 255, 255, 0.15);
            color: white;
            font-size: 1rem;
            transition: var(--transition);
        }
        .search-form input::placeholder {
            color: rgba(255, 255, 255, 0.7);
        }
        .search-form input:focus {
            outline: none;
            background: rgba(255, 255, 255, 0.25);
            box-shadow: 0 0 0 2px var(--secondary);
        }
        .search-form button {
            position: absolute;
            right: 5px;
            top: 50%;
            transform: translateY(-50%);
            background: var(--secondary);
            border: none;
            color: white;
            width: 40px;
            height: 40px;
            border-radius: 50%;
            cursor: pointer;
            transition: var(--transition);
        }
        .search-form button:hover {
            background: var(--accent);
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.8rem;
            cursor: pointer;
            padding: 5px;
        }
        nav {
            background: #34495e;
            margin-top: 1rem;
            border-radius: var(--radius);
        }
        .nav-list {
            display: flex;
            list-style: none;
            justify-content: center;
            flex-wrap: wrap;
        }
        .nav-list li {
            position: relative;
        }
        .nav-list a {
            color: white;
            padding: 15px 25px;
            display: block;
            font-weight: 600;
            text-transform: uppercase;
            font-size: 0.9rem;
            letter-spacing: 0.5px;
        }
        .nav-list a:hover,
        .nav-list a.active {
            background: var(--secondary);
            color: white;
        }
        .nav-list a i {
            margin-right: 8px;
        }
        .breadcrumb {
            padding: 15px 0;
            background: #e8f4fc;
            font-size: 0.9rem;
            color: #555;
        }
        .breadcrumb a {
            color: var(--secondary);
        }
        .breadcrumb span {
            margin: 0 8px;
            color: #999;
        }
        main {
            flex: 1;
            padding: 30px 0;
        }
        .article-container {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
        }
        @media (max-width: 992px) {
            .article-container {
                grid-template-columns: 1fr;
            }
        }
        .article-main {
            background: white;
            padding: 40px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .article-header {
            margin-bottom: 30px;
            border-bottom: 3px solid var(--light);
            padding-bottom: 20px;
        }
        .article-header h1 {
            font-size: 2.8rem;
            color: var(--primary);
            margin-bottom: 15px;
            line-height: 1.2;
        }
        .meta {
            display: flex;
            flex-wrap: wrap;
            gap: 20px;
            color: #7f8c8d;
            font-size: 0.9rem;
        }
        .meta span i {
            margin-right: 5px;
            color: var(--secondary);
        }
        .article-image {
            margin: 30px 0;
            text-align: center;
        }
        .article-image img {
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            width: 100%;
            max-height: 500px;
            object-fit: cover;
        }
        .article-image figcaption {
            font-style: italic;
            color: #666;
            margin-top: 10px;
            font-size: 0.9rem;
        }
        .article-content h2 {
            color: var(--primary);
            margin: 40px 0 20px;
            padding-bottom: 10px;
            border-bottom: 2px dashed var(--light);
            font-size: 2rem;
        }
        .article-content h3 {
            color: var(--secondary);
            margin: 30px 0 15px;
            font-size: 1.6rem;
        }
        .article-content p {
            margin-bottom: 20px;
            font-size: 1.1rem;
            text-align: justify;
        }
        .article-content blockquote {
            border-left: 5px solid var(--secondary);
            padding-left: 25px;
            margin: 30px 0;
            font-style: italic;
            color: #555;
            background: #f8f9fa;
            padding: 20px;
            border-radius: 0 var(--radius) var(--radius) 0;
        }
        .article-content ul, .article-content ol {
            margin-left: 30px;
            margin-bottom: 20px;
        }
        .article-content li {
            margin-bottom: 10px;
        }
        .highlight {
            background: #fffacd;
            padding: 20px;
            border-radius: var(--radius);
            border-left: 4px solid var(--warning);
            margin: 25px 0;
        }
        .highlight strong {
            color: var(--dark);
        }
        .term {
            font-weight: bold;
            color: var(--primary);
            border-bottom: 1px dotted var(--secondary);
        }
        .pro-tip {
            background: #e8f6f3;
            border: 1px solid var(--success);
            padding: 20px;
            border-radius: var(--radius);
            margin: 25px 0;
        }
        .pro-tip h4 {
            color: var(--success);
            margin-bottom: 10px;
            display: flex;
            align-items: center;
        }
        .pro-tip h4 i {
            margin-right: 10px;
        }
        .sidebar {
            display: flex;
            flex-direction: column;
            gap: 30px;
        }
        .sidebar-widget {
            background: white;
            padding: 25px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .sidebar-widget h3 {
            color: var(--primary);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--light);
            font-size: 1.4rem;
        }
        .rating-widget {
            text-align: center;
        }
        .stars {
            font-size: 2rem;
            color: #ddd;
            margin-bottom: 15px;
            cursor: pointer;
        }
        .stars .star {
            margin: 0 3px;
            transition: var(--transition);
        }
        .stars .star:hover,
        .stars .star.active {
            color: var(--warning);
        }
        .rating-form input,
        .rating-form textarea {
            width: 100%;
            padding: 12px;
            margin-bottom: 15px;
            border: 1px solid #ddd;
            border-radius: var(--radius);
            font-size: 1rem;
        }
        .rating-form button {
            background: var(--secondary);
            color: white;
            border: none;
            padding: 12px 25px;
            border-radius: var(--radius);
            cursor: pointer;
            font-weight: bold;
            transition: var(--transition);
            width: 100%;
        }
        .rating-form button:hover {
            background: var(--primary);
        }
        .comments-list {
            max-height: 400px;
            overflow-y: auto;
            padding-right: 10px;
        }
        .comment {
            padding: 15px 0;
            border-bottom: 1px solid #eee;
        }
        .comment:last-child {
            border-bottom: none;
        }
        .comment-header {
            display: flex;
            justify-content: space-between;
            margin-bottom: 8px;
            font-size: 0.9rem;
            color: #666;
        }
        .comment-user {
            font-weight: bold;
            color: var(--primary);
        }
        .longtail-links {
            background: var(--primary);
            padding: 40px 0;
            color: white;
        }
        .longtail-links .container {
            display: grid;
            grid-template-columns: repeat(5, 1fr);
            gap: 20px;
        }
        @media (max-width: 768px) {
            .longtail-links .container {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        .web-link {
            background: rgba(255, 255, 255, 0.05);
            padding: 15px;
            border-radius: var(--radius);
            transition: var(--transition);
        }
        .web-link:hover {
            background: rgba(255, 255, 255, 0.1);
            transform: translateY(-5px);
        }
        .web-link a {
            color: var(--light);
            font-weight: 600;
            display: block;
        }
        .web-link a:hover {
            color: var(--accent);
        }
        footer {
            background: #1a252f;
            color: #bdc3c7;
            padding: 40px 0 20px;
            text-align: center;
        }
        .footer-links {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 30px;
            margin-bottom: 30px;
        }
        .footer-links a {
            color: #ecf0f1;
            font-weight: 600;
        }
        .copyright {
            font-size: 0.9rem;
            border-top: 1px solid #2c3e50;
            padding-top: 20px;
            color: #95a5a6;
        }
        @media (max-width: 768px) {
            .header-top {
                flex-direction: column;
                align-items: stretch;
            }
            .logo {
                margin-bottom: 15px;
                text-align: center;
            }
            .search-form {
                margin: 15px 0;
                max-width: 100%;
            }
            .hamburger {
                display: block;
                position: absolute;
                top: 20px;
                right: 20px;
            }
            nav {
                display: none;
                margin-top: 0;
            }
            nav.active {
                display: block;
            }
            .nav-list {
                flex-direction: column;
            }
            .nav-list a {
                padding: 15px;
                border-bottom: 1px solid rgba(255, 255, 255, 0.1);
            }
            .article-main {
                padding: 25px;
            }
            .article-header h1 {
                font-size: 2.2rem;
            }
            .sidebar {
                order: -1;
            }
        }