:root {
            --primary-blue: #2a5c8a;
            --secondary-blue: #4a90e2;
            --accent-yellow: #f7b500;
            --light-bg: #f8f9fa;
            --dark-text: #2c3e50;
            --medium-gray: #6c757d;
            --light-gray: #e9ecef;
            --success-green: #28a745;
            --warning-orange: #fd7e14;
            --spacing-xs: 0.5rem;
            --spacing-sm: 1rem;
            --spacing-md: 2rem;
            --spacing-lg: 3rem;
            --spacing-xl: 5rem;
            --border-radius: 8px;
            --box-shadow: 0 4px 12px rgba(0,0,0,0.08);
            --transition: all 0.3s ease;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.7;
            color: var(--dark-text);
            background-color: #fff;
            overflow-x: hidden;
        }
        .site-header {
            background: linear-gradient(135deg, var(--primary-blue), #1a365d);
            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: 1280px;
            margin: 0 auto;
            padding: 0 var(--spacing-sm);
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .my-logo {
            font-size: 1.8rem;
            font-weight: 800;
            color: white;
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 10px;
            transition: var(--transition);
        }
        .my-logo:hover {
            color: var(--accent-yellow);
            transform: translateY(-2px);
        }
        .my-logo i {
            color: var(--accent-yellow);
        }
        .main-nav ul {
            display: flex;
            list-style: none;
            gap: var(--spacing-md);
        }
        .main-nav a {
            color: white;
            text-decoration: none;
            font-weight: 600;
            padding: 0.5rem 0;
            position: relative;
            transition: var(--transition);
        }
        .main-nav a:hover,
        .main-nav a.active {
            color: var(--accent-yellow);
        }
        .main-nav a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 3px;
            background: var(--accent-yellow);
            transition: width 0.3s ease;
        }
        .main-nav a:hover::after {
            width: 100%;
        }
        .mobile-toggle {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.5rem;
            cursor: pointer;
        }
        .breadcrumb {
            background-color: var(--light-bg);
            padding: 0.8rem var(--spacing-sm);
            font-size: 0.9rem;
            border-bottom: 1px solid var(--light-gray);
        }
        .breadcrumb a {
            color: var(--primary-blue);
            text-decoration: none;
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        .main-content {
            max-width: 1280px;
            margin: 0 auto;
            padding: var(--spacing-md) var(--spacing-sm);
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: var(--spacing-lg);
        }
        article {
            background: white;
            padding: var(--spacing-lg);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
        }
        .article-header {
            margin-bottom: var(--spacing-lg);
            border-bottom: 3px solid var(--accent-yellow);
            padding-bottom: var(--spacing-md);
        }
        .article-header h1 {
            font-size: 2.8rem;
            color: var(--primary-blue);
            line-height: 1.2;
            margin-bottom: var(--spacing-sm);
        }
        .meta-info {
            display: flex;
            gap: var(--spacing-md);
            color: var(--medium-gray);
            font-size: 0.9rem;
            flex-wrap: wrap;
        }
        .meta-info i {
            margin-right: 5px;
        }
        .content-section {
            margin-bottom: var(--spacing-xl);
        }
        h2 {
            font-size: 2rem;
            color: var(--primary-blue);
            margin: var(--spacing-lg) 0 var(--spacing-sm);
            padding-bottom: 0.5rem;
            border-bottom: 2px solid var(--light-gray);
        }
        h3 {
            font-size: 1.6rem;
            color: var(--secondary-blue);
            margin: var(--spacing-md) 0 var(--spacing-xs);
        }
        h4 {
            font-size: 1.3rem;
            color: var(--dark-text);
            margin: var(--spacing-sm) 0 var(--spacing-xs);
        }
        p {
            margin-bottom: 1.2rem;
            text-align: justify;
        }
        .highlight-box {
            background: linear-gradient(120deg, var(--light-bg), #e3f2fd);
            border-left: 5px solid var(--secondary-blue);
            padding: var(--spacing-md);
            margin: var(--spacing-md) 0;
            border-radius: 0 var(--border-radius) var(--border-radius) 0;
        }
        .key-point {
            background-color: #fff8e1;
            border: 1px dashed var(--accent-yellow);
            padding: var(--spacing-sm);
            margin: var(--spacing-sm) 0;
            border-radius: var(--border-radius);
        }
        .key-point strong {
            color: var(--primary-blue);
        }
        img {
            max-width: 100%;
            height: auto;
            border-radius: var(--border-radius);
            box-shadow: 0 6px 15px rgba(0,0,0,0.1);
            display: block;
            margin: var(--spacing-md) auto;
            transition: transform 0.5s ease;
        }
        img:hover {
            transform: scale(1.01);
        }
        .img-caption {
            text-align: center;
            font-style: italic;
            color: var(--medium-gray);
            margin-top: -0.5rem;
            margin-bottom: var(--spacing-md);
            font-size: 0.9rem;
        }
        a.content-link {
            color: var(--secondary-blue);
            text-decoration: none;
            border-bottom: 1px dotted var(--secondary-blue);
            font-weight: 600;
        }
        a.content-link:hover {
            color: var(--primary-blue);
            border-bottom-style: solid;
        }
        ul, ol {
            margin-left: 1.5rem;
            margin-bottom: 1.2rem;
        }
        li {
            margin-bottom: 0.5rem;
        }
        blockquote {
            font-style: italic;
            border-left: 4px solid var(--accent-yellow);
            padding-left: var(--spacing-md);
            margin: var(--spacing-md) 0;
            color: var(--medium-gray);
            background-color: var(--light-bg);
            padding: var(--spacing-md);
            border-radius: 0 var(--border-radius) var(--border-radius) 0;
        }
        .sidebar {
            display: flex;
            flex-direction: column;
            gap: var(--spacing-md);
        }
        .sidebar-widget {
            background: white;
            padding: var(--spacing-md);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
        }
        .sidebar-widget h3 {
            font-size: 1.3rem;
            color: var(--primary-blue);
            margin-top: 0;
            padding-bottom: 0.5rem;
            border-bottom: 1px solid var(--light-gray);
        }
        .search-box {
            display: flex;
            margin-top: 0.8rem;
        }
        .search-box input {
            flex: 1;
            padding: 0.8rem;
            border: 2px solid var(--light-gray);
            border-right: none;
            border-radius: var(--border-radius) 0 0 var(--border-radius);
            font-size: 1rem;
        }
        .search-box button {
            background: var(--secondary-blue);
            color: white;
            border: none;
            padding: 0 1.2rem;
            border-radius: 0 var(--border-radius) var(--border-radius) 0;
            cursor: pointer;
            transition: var(--transition);
        }
        .search-box button:hover {
            background: var(--primary-blue);
        }
        .rating-widget {
            text-align: center;
        }
        .stars {
            font-size: 1.8rem;
            color: var(--light-gray);
            margin: 0.5rem 0;
            cursor: pointer;
        }
        .stars .active {
            color: var(--accent-yellow);
        }
        .rating-result {
            font-weight: bold;
            color: var(--primary-blue);
            margin-top: 0.5rem;
        }
        .related-links ul {
            list-style: none;
            margin-left: 0;
        }
        .related-links li {
            margin-bottom: 0.8rem;
            padding-bottom: 0.8rem;
            border-bottom: 1px dotted var(--light-gray);
        }
        .related-links a {
            color: var(--dark-text);
            text-decoration: none;
            transition: var(--transition);
            display: block;
        }
        .related-links a:hover {
            color: var(--secondary-blue);
            padding-left: 5px;
        }
        .related-links i {
            color: var(--secondary-blue);
            margin-right: 8px;
        }
        .comments-section {
            margin-top: var(--spacing-xl);
            padding-top: var(--spacing-lg);
            border-top: 3px solid var(--light-gray);
        }
        .comment-form {
            background: var(--light-bg);
            padding: var(--spacing-md);
            border-radius: var(--border-radius);
            margin-bottom: var(--spacing-lg);
        }
        .form-group {
            margin-bottom: var(--spacing-sm);
        }
        .form-group label {
            display: block;
            margin-bottom: 0.3rem;
            font-weight: 600;
        }
        .form-control {
            width: 100%;
            padding: 0.8rem;
            border: 2px solid var(--light-gray);
            border-radius: var(--border-radius);
            font-size: 1rem;
            transition: border-color 0.3s;
        }
        .form-control:focus {
            border-color: var(--secondary-blue);
            outline: none;
        }
        textarea.form-control {
            min-height: 120px;
            resize: vertical;
        }
        .submit-btn {
            background: var(--secondary-blue);
            color: white;
            border: none;
            padding: 0.8rem 1.8rem;
            border-radius: var(--border-radius);
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
        }
        .submit-btn:hover {
            background: var(--primary-blue);
            transform: translateY(-2px);
        }
        .comment {
            background: white;
            padding: var(--spacing-md);
            border-radius: var(--border-radius);
            margin-bottom: var(--spacing-md);
            border-left: 4px solid var(--secondary-blue);
            box-shadow: 0 3px 8px rgba(0,0,0,0.05);
        }
        .comment-header {
            display: flex;
            justify-content: space-between;
            margin-bottom: 0.5rem;
            color: var(--medium-gray);
            font-size: 0.9rem;
        }
        .comment-author {
            font-weight: bold;
            color: var(--primary-blue);
        }
        .site-footer {
            background: linear-gradient(135deg, #1a365d, var(--primary-blue));
            color: white;
            padding: var(--spacing-xl) var(--spacing-sm) var(--spacing-md);
            margin-top: var(--spacing-xl);
        }
        .footer-container {
            max-width: 1280px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: var(--spacing-lg);
        }
        .footer-logo {
            font-size: 1.8rem;
            font-weight: 800;
            margin-bottom: var(--spacing-sm);
        }
        .footer-links h4 {
            color: var(--accent-yellow);
            margin-bottom: var(--spacing-sm);
            font-size: 1.2rem;
        }
        .footer-links ul {
            list-style: none;
            margin-left: 0;
        }
        .footer-links li {
            margin-bottom: 0.6rem;
        }
        .footer-links a {
            color: #d1d8e0;
            text-decoration: none;
            transition: var(--transition);
        }
        .footer-links a:hover {
            color: white;
            padding-left: 5px;
        }
        friend-link {
            display: block;
            padding: 0.8rem;
            background: rgba(255,255,255,0.1);
            border-radius: var(--border-radius);
            margin-bottom: 0.5rem;
            text-align: center;
        }
        friend-link a {
            color: white;
            text-decoration: none;
            font-weight: 600;
        }
        friend-link a:hover {
            color: var(--accent-yellow);
        }
        .copyright {
            text-align: center;
            margin-top: var(--spacing-xl);
            padding-top: var(--spacing-md);
            border-top: 1px solid rgba(255,255,255,0.2);
            color: #b0bec5;
            font-size: 0.9rem;
        }
        @media (max-width: 1024px) {
            .main-content {
                grid-template-columns: 1fr;
            }
            .sidebar {
                order: -1;
                display: grid;
                grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
                gap: var(--spacing-md);
            }
        }
        @media (max-width: 768px) {
            .header-container {
                flex-wrap: wrap;
            }
            .main-nav {
                width: 100%;
                display: none;
                margin-top: 1rem;
            }
            .main-nav.active {
                display: block;
            }
            .main-nav ul {
                flex-direction: column;
                gap: 0;
            }
            .main-nav li {
                width: 100%;
                border-bottom: 1px solid rgba(255,255,255,0.1);
            }
            .main-nav a {
                display: block;
                padding: 0.8rem;
            }
            .mobile-toggle {
                display: block;
            }
            .article-header h1 {
                font-size: 2.2rem;
            }
            h2 {
                font-size: 1.8rem;
            }
            h3 {
                font-size: 1.4rem;
            }
            .main-content {
                padding: var(--spacing-sm);
            }
            article {
                padding: var(--spacing-md);
            }
        }
        @media (max-width: 480px) {
            .article-header h1 {
                font-size: 1.8rem;
            }
            .meta-info {
                flex-direction: column;
                gap: 0.5rem;
            }
            .footer-container {
                grid-template-columns: 1fr;
            }
        }
        @media print {
            .site-header,
            .sidebar,
            .comments-section,
            .site-footer,
            .mobile-toggle,
            .search-box,
            .rating-widget {
                display: none;
            }
            body {
                color: black;
                background: white;
            }
            a {
                color: black;
                text-decoration: underline;
            }
            .main-content {
                grid-template-columns: 1fr;
                max-width: 100%;
                padding: 0;
            }
            article {
                box-shadow: none;
                padding: 0;
            }
        }