:root {
            --primary: #4361ee;
            --secondary: #3a0ca3;
            --accent: #f72585;
            --light: #f8f9fa;
            --dark: #212529;
            --gray: #6c757d;
            --light-gray: #e9ecef;
            --border-radius: 12px;
            --shadow: 0 5px 15px rgba(0,0,0,0.08);
            --transition: all 0.3s ease;
            --max-width: 1200px;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
            line-height: 1.7;
            color: var(--dark);
            background-color: #fff;
            overflow-x: hidden;
        }
        a {
            color: var(--primary);
            text-decoration: none;
            transition: var(--transition);
        }
        a:hover {
            color: var(--accent);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        .container {
            width: 100%;
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 20px;
        }
        section, article, header, footer {
            padding: 60px 0;
        }
        h1, h2, h3, h4 {
            color: var(--secondary);
            margin-bottom: 1.2rem;
            line-height: 1.3;
            font-weight: 700;
        }
        h1 {
            font-size: clamp(2.2rem, 5vw, 3.2rem);
            margin-bottom: 1.5rem;
            color: var(--primary);
        }
        h2 {
            font-size: clamp(1.8rem, 4vw, 2.4rem);
            border-bottom: 3px solid var(--light-gray);
            padding-bottom: 0.7rem;
            margin-top: 2.5rem;
        }
        h3 {
            font-size: clamp(1.5rem, 3vw, 1.9rem);
            margin-top: 2rem;
        }
        h4 {
            font-size: 1.3rem;
            margin-top: 1.5rem;
        }
        p {
            margin-bottom: 1.5rem;
            font-size: 1.1rem;
        }
        .lead {
            font-size: 1.3rem;
            color: var(--gray);
            font-weight: 300;
        }
        strong, b {
            font-weight: 700;
            color: var(--secondary);
        }
        em {
            font-style: italic;
        }
        blockquote {
            border-left: 4px solid var(--accent);
            padding-left: 1.5rem;
            margin: 2rem 0;
            font-style: italic;
            color: var(--gray);
            background: var(--light);
            padding: 1.5rem;
            border-radius: 0 var(--border-radius) var(--border-radius) 0;
        }
        ul, ol {
            margin-bottom: 1.5rem;
            padding-left: 2rem;
        }
        li {
            margin-bottom: 0.7rem;
        }
        .text-center {
            text-align: center;
        }
        .article-intro {
            background: linear-gradient(135deg, #f0f4ff 0%, #e6f7ff 100%);
            padding: 2.5rem;
            border-radius: var(--border-radius);
            margin: 2.5rem 0;
            border-left: 5px solid var(--primary);
        }
        .key-takeaways {
            background-color: #fff9db;
            border: 2px dashed #ffd43b;
            padding: 2rem;
            border-radius: var(--border-radius);
            margin: 2.5rem 0;
        }
        .key-takeaways h3 {
            color: #e67700;
            margin-top: 0;
        }
        .btn {
            display: inline-block;
            padding: 0.9rem 1.8rem;
            background-color: var(--primary);
            color: white;
            border: none;
            border-radius: 50px;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            text-align: center;
            font-size: 1rem;
        }
        .btn:hover {
            background-color: var(--secondary);
            color: white;
            transform: translateY(-3px);
            box-shadow: var(--shadow);
        }
        .btn-accent {
            background-color: var(--accent);
        }
        .site-header {
            background-color: white;
            box-shadow: 0 2px 10px rgba(0,0,0,0.05);
            position: sticky;
            top: 0;
            z-index: 1000;
            padding: 15px 0;
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .my-logo {
            font-size: 1.8rem;
            font-weight: 900;
            color: var(--primary);
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .my-logo a {
            color: inherit;
        }
        .my-logo i {
            color: var(--accent);
        }
        .main-nav ul {
            display: flex;
            list-style: none;
            gap: 2rem;
        }
        .main-nav a {
            font-weight: 600;
            color: var(--dark);
            font-size: 1rem;
        }
        .main-nav a:hover {
            color: var(--accent);
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            background: none;
            border: none;
            color: var(--primary);
            cursor: pointer;
        }
        .breadcrumb {
            padding: 1rem 0;
            background-color: var(--light);
            font-size: 0.9rem;
        }
        .breadcrumb ol {
            display: flex;
            list-style: none;
            padding: 0;
            margin: 0;
            flex-wrap: wrap;
        }
        .breadcrumb li:not(:last-child)::after {
            content: "/";
            margin: 0 10px;
            color: var(--gray);
        }
        .breadcrumb a {
            color: var(--gray);
        }
        .breadcrumb a:hover {
            color: var(--primary);
        }
        .search-section {
            background-color: var(--light);
            padding: 2rem 0;
        }
        .search-form {
            max-width: 700px;
            margin: 0 auto;
            display: flex;
            border-radius: 50px;
            overflow: hidden;
            box-shadow: var(--shadow);
        }
        .search-input {
            flex-grow: 1;
            padding: 1rem 1.5rem;
            border: none;
            font-size: 1rem;
        }
        .search-btn {
            background-color: var(--primary);
            color: white;
            border: none;
            padding: 0 2rem;
            cursor: pointer;
            font-size: 1.1rem;
        }
        .search-btn:hover {
            background-color: var(--secondary);
        }
        .main-content {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 3rem;
            align-items: start;
        }
        @media (max-width: 992px) {
            .main-content {
                grid-template-columns: 1fr;
            }
        }
        .article-body {
            min-height: 5000px; 
        }
        .sidebar {
            position: sticky;
            top: 120px;
            background: var(--light);
            border-radius: var(--border-radius);
            padding: 2rem;
            box-shadow: var(--shadow);
        }
        .sidebar h3 {
            margin-top: 0;
            color: var(--primary);
        }
        .sidebar ul {
            list-style: none;
            padding: 0;
        }
        .sidebar li {
            margin-bottom: 0.8rem;
        }
        .sidebar a {
            display: block;
            padding: 0.7rem;
            background: white;
            border-radius: 8px;
            border-left: 4px solid var(--primary);
        }
        .sidebar a:hover {
            background-color: #e3f2fd;
            border-left-color: var(--accent);
        }
        .article-image {
            margin: 2.5rem 0;
            border-radius: var(--border-radius);
            overflow: hidden;
            box-shadow: var(--shadow);
        }
        .article-image figcaption {
            padding: 1rem;
            background: var(--light);
            font-size: 0.9rem;
            color: var(--gray);
            text-align: center;
        }
        .rating-section, .comment-section {
            background-color: var(--light);
            padding: 2.5rem;
            border-radius: var(--border-radius);
            margin: 3rem 0;
        }
        .rating-section h2, .comment-section h2 {
            border: none;
        }
        .star-rating {
            display: flex;
            gap: 5px;
            margin: 1rem 0 2rem;
            font-size: 2rem;
            color: #ffc107;
        }
        .star-rating i {
            cursor: pointer;
            transition: var(--transition);
        }
        .star-rating i:hover {
            transform: scale(1.2);
        }
        .rating-form, .comment-form {
            display: grid;
            gap: 1.2rem;
            max-width: 600px;
        }
        .form-group label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 600;
        }
        .form-control {
            width: 100%;
            padding: 0.9rem;
            border: 1px solid #ced4da;
            border-radius: 8px;
            font-size: 1rem;
            transition: var(--transition);
        }
        .form-control:focus {
            outline: none;
            border-color: var(--primary);
            box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2);
        }
        textarea.form-control {
            min-height: 150px;
            resize: vertical;
        }
        .site-footer {
            background-color: var(--dark);
            color: white;
            padding: 4rem 0 2rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 3rem;
            margin-bottom: 3rem;
        }
        .footer-section h3 {
            color: white;
            margin-bottom: 1.5rem;
            font-size: 1.4rem;
        }
        .footer-links {
            list-style: none;
            padding: 0;
        }
        .footer-links li {
            margin-bottom: 0.8rem;
        }
        .footer-links a {
            color: #adb5bd;
        }
        .footer-links a:hover {
            color: white;
            padding-left: 5px;
        }
        friend-link {
            display: block;
            background: rgba(255,255,255,0.05);
            padding: 1.5rem;
            border-radius: var(--border-radius);
            margin: 1.5rem 0;
        }
        friend-link a {
            color: #4dabf7;
            font-weight: 600;
        }
        .copyright {
            text-align: center;
            padding-top: 2rem;
            border-top: 1px solid #495057;
            color: #adb5bd;
            font-size: 0.9rem;
        }
        .update-time {
            background-color: #d1ecf1;
            color: #0c5460;
            padding: 1rem;
            border-radius: 8px;
            margin: 2rem 0;
            display: inline-flex;
            align-items: center;
            gap: 10px;
        }
        @media (max-width: 768px) {
            .header-container {
                flex-wrap: wrap;
            }
            .main-nav {
                display: none;
                width: 100%;
                order: 3;
                margin-top: 1rem;
            }
            .main-nav.active {
                display: block;
            }
            .main-nav ul {
                flex-direction: column;
                gap: 0;
            }
            .main-nav li {
                border-bottom: 1px solid var(--light-gray);
            }
            .main-nav a {
                display: block;
                padding: 1rem;
            }
            .hamburger {
                display: block;
            }
            section, article, header, footer {
                padding: 40px 0;
            }
            .article-intro, .key-takeaways, .rating-section, .comment-section {
                padding: 1.8rem;
            }
        }