:root {
            --primary: #1a237e;
            --primary-light: #534bae;
            --primary-dark: #000051;
            --secondary: #ff9800;
            --secondary-light: #ffc947;
            --secondary-dark: #c66900;
            --accent: #4caf50;
            --text-primary: #212121;
            --text-secondary: #757575;
            --bg-light: #f5f5f5;
            --bg-white: #ffffff;
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
            --border-radius: 12px;
            --transition: all 0.3s ease;
        }
        * {
            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: var(--text-primary);
            background-color: var(--bg-light);
            overflow-x: hidden;
        }
        .site-header {
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            color: white;
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 2px 15px rgba(0, 0, 0, 0.2);
        }
        .header-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 80px;
        }
        .my-logo {
            font-size: 2.2rem;
            font-weight: 800;
            color: white;
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 10px;
            transition: var(--transition);
        }
        .my-logo:hover {
            color: var(--secondary-light);
            transform: scale(1.02);
        }
        .my-logo span {
            color: var(--secondary);
        }
        .main-nav ul {
            display: flex;
            list-style: none;
            gap: 30px;
        }
        .main-nav a {
            color: white;
            text-decoration: none;
            font-weight: 600;
            font-size: 1.05rem;
            padding: 8px 0;
            position: relative;
            transition: var(--transition);
        }
        .main-nav a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 3px;
            background: var(--secondary);
            transition: width 0.3s ease;
        }
        .main-nav a:hover::after,
        .main-nav a.active::after {
            width: 100%;
        }
        .main-nav a:hover {
            color: var(--secondary-light);
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            background: none;
            border: none;
            color: white;
            cursor: pointer;
        }
        .breadcrumb {
            max-width: 1200px;
            margin: 20px auto;
            padding: 0 20px;
        }
        .breadcrumb nav ol {
            display: flex;
            list-style: none;
            flex-wrap: wrap;
            gap: 8px;
        }
        .breadcrumb li {
            display: flex;
            align-items: center;
        }
        .breadcrumb a {
            color: var(--primary);
            text-decoration: none;
            font-weight: 500;
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        .breadcrumb li:not(:last-child)::after {
            content: '/';
            margin-left: 8px;
            color: var(--text-secondary);
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 20px;
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 40px;
        }
        @media (max-width: 992px) {
            .container {
                grid-template-columns: 1fr;
            }
        }
        .content-main {
            background: var(--bg-white);
            border-radius: var(--border-radius);
            padding: 40px;
            box-shadow: var(--shadow);
        }
        .sidebar {
            background: var(--bg-white);
            border-radius: var(--border-radius);
            padding: 25px;
            box-shadow: var(--shadow);
            align-self: start;
            position: sticky;
            top: 100px;
        }
        h1, h2, h3, h4 {
            color: var(--primary);
            line-height: 1.3;
            margin-top: 1.5em;
            margin-bottom: 0.7em;
        }
        h1 {
            font-size: 2.8rem;
            border-bottom: 3px solid var(--secondary);
            padding-bottom: 15px;
            margin-top: 0;
        }
        h2 {
            font-size: 2rem;
            padding-left: 10px;
            border-left: 5px solid var(--accent);
        }
        h3 {
            font-size: 1.6rem;
            color: var(--primary-light);
        }
        h4 {
            font-size: 1.3rem;
            color: var(--text-primary);
        }
        p {
            margin-bottom: 1.5em;
            text-align: justify;
        }
        .lead {
            font-size: 1.3rem;
            font-weight: 500;
            color: var(--primary);
            background: #e8f5e9;
            padding: 20px;
            border-radius: var(--border-radius);
            border-left: 5px solid var(--accent);
        }
        .highlight {
            background: linear-gradient(120deg, #ffecb3 0%, #ffecb3 100%);
            padding: 3px 6px;
            border-radius: 4px;
            font-weight: 600;
        }
        strong {
            color: var(--primary-dark);
        }
        .emoji {
            font-size: 1.2em;
            margin-right: 5px;
        }
        .article-img {
            width: 100%;
            max-height: 500px;
            object-fit: cover;
            border-radius: var(--border-radius);
            margin: 30px 0;
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
            transition: transform 0.5s ease;
        }
        .article-img:hover {
            transform: scale(1.01);
        }
        ul, ol {
            margin-left: 25px;
            margin-bottom: 1.5em;
        }
        li {
            margin-bottom: 0.7em;
        }
        .search-box {
            background: var(--bg-light);
            border-radius: 50px;
            padding: 15px 25px;
            display: flex;
            gap: 10px;
            margin: 30px 0;
            border: 2px solid transparent;
            transition: var(--transition);
        }
        .search-box:focus-within {
            border-color: var(--secondary);
            background: white;
        }
        .search-box input {
            flex: 1;
            border: none;
            background: transparent;
            font-size: 1.1rem;
            outline: none;
        }
        .search-box button {
            background: var(--secondary);
            color: white;
            border: none;
            border-radius: 50%;
            width: 50px;
            height: 50px;
            cursor: pointer;
            transition: var(--transition);
        }
        .search-box button:hover {
            background: var(--secondary-dark);
            transform: rotate(10deg);
        }
        .user-interaction {
            background: #f0f7ff;
            border-radius: var(--border-radius);
            padding: 30px;
            margin: 40px 0;
            border: 1px dashed var(--primary-light);
        }
        .rating-form, .comment-form {
            margin-top: 20px;
        }
        .stars {
            display: flex;
            gap: 10px;
            margin: 15px 0;
        }
        .star {
            font-size: 2rem;
            color: #ddd;
            cursor: pointer;
            transition: color 0.2s;
        }
        .star:hover,
        .star.active {
            color: #ffc107;
        }
        .form-group {
            margin-bottom: 20px;
        }
        label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: var(--primary);
        }
        input, textarea, select {
            width: 100%;
            padding: 15px;
            border: 2px solid #e0e0e0;
            border-radius: 8px;
            font-family: inherit;
            font-size: 1rem;
            transition: var(--transition);
        }
        input:focus, textarea:focus {
            outline: none;
            border-color: var(--secondary);
        }
        button[type="submit"] {
            background: linear-gradient(to right, var(--primary), var(--primary-light));
            color: white;
            border: none;
            padding: 15px 30px;
            border-radius: 8px;
            font-size: 1.1rem;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            display: inline-flex;
            align-items: center;
            gap: 10px;
        }
        button[type="submit"]:hover {
            background: linear-gradient(to right, var(--primary-dark), var(--primary));
            transform: translateY(-3px);
            box-shadow: 0 7px 14px rgba(0, 0, 0, 0.1);
        }
        a.content-link {
            color: var(--primary-light);
            text-decoration: none;
            font-weight: 600;
            border-bottom: 2px dotted var(--primary-light);
            transition: var(--transition);
        }
        a.content-link:hover {
            color: var(--secondary-dark);
            border-bottom-style: solid;
        }
        .sidebar-widget {
            margin-bottom: 35px;
        }
        .sidebar-widget h3 {
            font-size: 1.4rem;
            margin-top: 0;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--secondary-light);
        }
        .related-links ul {
            list-style: none;
            margin-left: 0;
        }
        .related-links li {
            padding: 12px 0;
            border-bottom: 1px solid #eee;
        }
        .related-links li:last-child {
            border-bottom: none;
        }
        .related-links a {
            text-decoration: none;
            color: var(--text-primary);
            display: flex;
            align-items: center;
            gap: 10px;
            transition: var(--transition);
        }
        .related-links a:hover {
            color: var(--secondary);
            padding-left: 10px;
        }
        .related-links i {
            color: var(--primary);
        }
        .update-time {
            background: #e3f2fd;
            padding: 15px;
            border-radius: 8px;
            font-size: 0.95rem;
            text-align: center;
        }
        .site-footer {
            background: var(--primary-dark);
            color: white;
            margin-top: 60px;
            padding-top: 50px;
        }
        .footer-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px 30px;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 40px;
        }
        .footer-logo {
            font-size: 2rem;
            font-weight: 800;
            color: white;
            margin-bottom: 20px;
            display: block;
        }
        .footer-logo span {
            color: var(--secondary);
        }
        friend-link {
            display: block;
            background: rgba(255, 255, 255, 0.05);
            padding: 15px;
            border-radius: 8px;
            margin-bottom: 15px;
        }
        friend-link a {
            color: var(--secondary-light);
            text-decoration: none;
            font-weight: 600;
            display: flex;
            align-items: center;
            gap: 10px;
            transition: var(--transition);
        }
        friend-link a:hover {
            color: white;
        }
        .copyright {
            text-align: center;
            padding: 25px;
            background: rgba(0, 0, 0, 0.3);
            font-size: 0.9rem;
            color: #ccc;
        }
        @media (max-width: 768px) {
            .header-container {
                height: 70px;
            }
            .my-logo {
                font-size: 1.8rem;
            }
            .main-nav ul {
                position: fixed;
                top: 70px;
                left: -100%;
                width: 100%;
                height: calc(100vh - 70px);
                background: var(--primary-dark);
                flex-direction: column;
                align-items: center;
                padding-top: 40px;
                gap: 25px;
                transition: left 0.4s ease;
                z-index: 999;
            }
            .main-nav.active ul {
                left: 0;
            }
            .hamburger {
                display: block;
            }
            h1 {
                font-size: 2.2rem;
            }
            h2 {
                font-size: 1.7rem;
            }
            h3 {
                font-size: 1.4rem;
            }
            .content-main {
                padding: 25px;
            }
            .sidebar {
                position: static;
            }
        }