:root {
            --primary: #2ecc71;
            --primary-dark: #27ae60;
            --secondary: #3498db;
            --dark: #2c3e50;
            --light: #ecf0f1;
            --gray: #95a5a6;
            --shadow: 0 4px 12px rgba(0,0,0,0.1);
            --transition: all 0.3s ease;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        body {
            background-color: #f9f9f9;
            color: #333;
            line-height: 1.7;
            overflow-x: hidden;
        }
        a {
            color: var(--secondary);
            text-decoration: none;
            transition: var(--transition);
        }
        a:hover {
            color: var(--primary-dark);
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        header {
            background-color: var(--dark);
            color: white;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 15px 0;
        }
        .my-logo {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--primary);
            text-transform: uppercase;
            letter-spacing: 1px;
        }
        .my-logo span {
            color: white;
        }
        .search-box {
            display: flex;
            flex-grow: 1;
            max-width: 400px;
            margin: 0 30px;
        }
        .search-box input {
            flex-grow: 1;
            padding: 10px 15px;
            border: none;
            border-radius: 4px 0 0 4px;
            font-size: 1rem;
        }
        .search-box button {
            background-color: var(--primary);
            color: white;
            border: none;
            padding: 0 20px;
            border-radius: 0 4px 4px 0;
            cursor: pointer;
            transition: var(--transition);
        }
        .search-box button:hover {
            background-color: var(--primary-dark);
        }
        .nav-toggle {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.5rem;
            cursor: pointer;
        }
        nav {
            background-color: rgba(44, 62, 80, 0.98);
            border-top: 1px solid rgba(255,255,255,0.1);
        }
        .nav-list {
            display: flex;
            list-style: none;
            justify-content: center;
        }
        .nav-list li {
            position: relative;
        }
        .nav-list a {
            color: white;
            padding: 18px 22px;
            display: block;
            font-weight: 500;
        }
        .nav-list a:hover {
            background-color: rgba(52, 152, 219, 0.2);
            color: var(--primary);
        }
        .breadcrumb {
            padding: 15px 0;
            background-color: #e8f4fc;
            font-size: 0.9rem;
        }
        .breadcrumb a {
            color: var(--dark);
        }
        .breadcrumb a:hover {
            color: var(--secondary);
        }
        .breadcrumb span {
            color: var(--gray);
            margin: 0 5px;
        }
        main {
            padding: 30px 0;
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
        }
        .content-area {
            background: white;
            border-radius: 10px;
            padding: 40px;
            box-shadow: var(--shadow);
        }
        h1 {
            color: var(--dark);
            font-size: 2.8rem;
            margin-bottom: 20px;
            line-height: 1.2;
        }
        .article-meta {
            color: var(--gray);
            margin-bottom: 30px;
            padding-bottom: 20px;
            border-bottom: 1px solid #eee;
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 10px;
        }
        .update-time {
            color: var(--primary-dark);
            font-weight: 500;
        }
        h2 {
            color: var(--dark);
            font-size: 2rem;
            margin: 40px 0 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--primary);
        }
        h3 {
            color: var(--secondary);
            font-size: 1.6rem;
            margin: 30px 0 15px;
        }
        h4 {
            color: var(--dark);
            font-size: 1.3rem;
            margin: 25px 0 10px;
        }
        p {
            margin-bottom: 20px;
            font-size: 1.1rem;
            text-align: justify;
        }
        .highlight {
            background-color: #f0f9ff;
            border-left: 4px solid var(--secondary);
            padding: 20px;
            margin: 25px 0;
            border-radius: 0 8px 8px 0;
        }
        .img-container {
            margin: 30px 0;
            text-align: center;
        }
        .feature-img {
            max-width: 100%;
            height: auto;
            border-radius: 10px;
            box-shadow: var(--shadow);
        }
        .caption {
            font-style: italic;
            color: var(--gray);
            margin-top: 10px;
            font-size: 0.95rem;
        }
        ul, ol {
            margin-left: 25px;
            margin-bottom: 20px;
        }
        li {
            margin-bottom: 8px;
        }
        strong {
            color: var(--dark);
            font-weight: 700;
        }
        .interaction-box {
            background-color: #f8f9fa;
            border-radius: 10px;
            padding: 25px;
            margin: 40px 0;
            border: 1px solid #dee2e6;
        }
        .interaction-box h3 {
            margin-top: 0;
            color: var(--dark);
        }
        .rating {
            margin: 20px 0;
            display: flex;
            align-items: center;
            gap: 10px;
            flex-wrap: wrap;
        }
        .stars {
            color: #ffc107;
            font-size: 1.5rem;
        }
        .stars i {
            cursor: pointer;
            transition: var(--transition);
        }
        .stars i:hover {
            transform: scale(1.2);
        }
        .form-group {
            margin-bottom: 20px;
        }
        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: var(--dark);
        }
        .form-group input,
        .form-group textarea,
        .form-group select {
            width: 100%;
            padding: 12px 15px;
            border: 1px solid #ccc;
            border-radius: 5px;
            font-size: 1rem;
            transition: var(--transition);
        }
        .form-group input:focus,
        .form-group textarea:focus {
            border-color: var(--secondary);
            outline: none;
            box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
        }
        button[type="submit"] {
            background-color: var(--primary);
            color: white;
            border: none;
            padding: 14px 28px;
            border-radius: 5px;
            font-size: 1.1rem;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
        }
        button[type="submit"]:hover {
            background-color: var(--primary-dark);
        }
        .sidebar {
            background: white;
            border-radius: 10px;
            padding: 25px;
            box-shadow: var(--shadow);
            align-self: start;
            position: sticky;
            top: 100px;
        }
        .sidebar h3 {
            font-size: 1.4rem;
            margin-top: 0;
            color: var(--dark);
            padding-bottom: 10px;
            border-bottom: 1px solid #eee;
        }
        .link-list {
            list-style: none;
            margin-left: 0;
        }
        .link-list li {
            margin-bottom: 12px;
            padding-bottom: 12px;
            border-bottom: 1px dashed #eee;
        }
        .link-list a {
            display: flex;
            align-items: center;
            gap: 10px;
            color: var(--dark);
        }
        .link-list a:hover {
            color: var(--primary);
        }
        .link-list i {
            color: var(--primary);
        }
        footer {
            background-color: var(--dark);
            color: white;
            padding: 50px 0 20px;
            margin-top: 50px;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 40px;
            margin-bottom: 40px;
        }
        .footer-logo {
            font-size: 1.8rem;
            font-weight: 800;
            color: var(--primary);
            margin-bottom: 15px;
        }
        .footer-about p {
            color: #bbb;
            font-size: 1rem;
        }
        friend-link {
            display: block;
            margin-top: 15px;
            color: #bbb;
            font-size: 0.9rem;
        }
        friend-link a {
            color: #bbb;
            margin-right: 15px;
        }
        friend-link a:hover {
            color: white;
        }
        .copyright {
            text-align: center;
            padding-top: 20px;
            border-top: 1px solid rgba(255,255,255,0.1);
            color: #bbb;
            font-size: 0.9rem;
        }
        @media (max-width: 992px) {
            main {
                grid-template-columns: 1fr;
            }
            .sidebar {
                position: static;
            }
        }
        @media (max-width: 768px) {
            .header-top {
                flex-wrap: wrap;
            }
            .search-box {
                order: 3;
                max-width: 100%;
                margin: 15px 0 0;
            }
            .nav-toggle {
                display: block;
            }
            nav {
                display: none;
                position: absolute;
                top: 100%;
                left: 0;
                width: 100%;
                box-shadow: var(--shadow);
            }
            .nav-list {
                flex-direction: column;
            }
            .nav-list a {
                padding: 15px 20px;
            }
            nav.active {
                display: block;
            }
            h1 {
                font-size: 2.2rem;
            }
            h2 {
                font-size: 1.8rem;
            }
            .content-area {
                padding: 25px;
            }
        }
        @media (max-width: 480px) {
            .header-top {
                flex-direction: column;
                align-items: flex-start;
            }
            .my-logo {
                margin-bottom: 15px;
            }
            .search-box {
                margin-top: 10px;
                width: 100%;
            }
        }