:root {
            --primary-green: #4CAF50;
            --secondary-green: #8BC34A;
            --accent-yellow: #FFC107;
            --dark-brown: #5D4037;
            --light-brown: #D7CCC8;
            --background: #F9F6F2;
            --text-dark: #333333;
            --text-light: #666666;
            --white: #FFFFFF;
            --shadow: rgba(0, 0, 0, 0.1);
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.8;
            color: var(--text-dark);
            background-color: var(--background);
            background-image: url('data:image/svg+xml;utf8,<svg width="100" height="100" viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"><path d="M0,0 L100,0 L100,100 Z" fill="%234CAF50" opacity="0.03"/></svg>');
            background-size: 200px;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        header {
            background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
            color: var(--white);
            padding: 1rem 0;
            box-shadow: 0 4px 12px var(--shadow);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
        }
        .my-logo {
            font-family: 'Comic Sans MS', cursive, sans-serif;
            font-size: 2.2rem;
            font-weight: 900;
            color: var(--accent-yellow);
            text-decoration: none;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
            transition: transform 0.3s ease;
        }
        .my-logo:hover {
            transform: scale(1.05);
        }
        .my-logo span {
            color: var(--white);
            font-size: 1.8rem;
        }
        .search-form {
            display: flex;
            flex: 0 1 400px;
            min-width: 250px;
        }
        .search-form input {
            flex-grow: 1;
            padding: 12px 20px;
            border: none;
            border-radius: 50px 0 0 50px;
            font-size: 1rem;
            outline: none;
        }
        .search-form button {
            background: var(--dark-brown);
            color: var(--white);
            border: none;
            padding: 12px 25px;
            border-radius: 0 50px 50px 0;
            cursor: pointer;
            transition: background 0.3s ease;
        }
        .search-form button:hover {
            background: #3E2723;
        }
        .mobile-toggle {
            display: none;
            font-size: 1.8rem;
            background: none;
            border: none;
            color: var(--white);
            cursor: pointer;
        }
        nav {
            background: var(--dark-brown);
            margin-top: 1rem;
            border-radius: 10px;
        }
        .nav-list {
            display: flex;
            list-style: none;
            justify-content: space-around;
            flex-wrap: wrap;
        }
        .nav-list li {
            flex: 1;
            text-align: center;
            min-width: 120px;
        }
        .nav-list a {
            color: var(--white);
            text-decoration: none;
            padding: 15px 10px;
            display: block;
            font-weight: 600;
            transition: all 0.3s ease;
            border-bottom: 3px solid transparent;
        }
        .nav-list a:hover,
        .nav-list a.active {
            background: rgba(255,255,255,0.1);
            border-bottom-color: var(--accent-yellow);
        }
        .breadcrumb {
            padding: 1rem 0;
            font-size: 0.9rem;
            color: var(--text-light);
        }
        .breadcrumb a {
            color: var(--primary-green);
            text-decoration: none;
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        .breadcrumb span {
            margin: 0 8px;
            color: var(--text-light);
        }
        main {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 2.5rem;
            margin: 2rem 0;
        }
        @media (max-width: 900px) {
            main {
                grid-template-columns: 1fr;
            }
        }
        .article-content {
            background: var(--white);
            padding: 2.5rem;
            border-radius: 15px;
            box-shadow: 0 6px 20px var(--shadow);
        }
        .article-header {
            border-bottom: 3px solid var(--primary-green);
            padding-bottom: 1.5rem;
            margin-bottom: 2.5rem;
        }
        h1 {
            font-size: 2.8rem;
            color: var(--primary-green);
            margin-bottom: 1rem;
            line-height: 1.3;
        }
        .article-meta {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            color: var(--text-light);
            font-size: 0.95rem;
            margin-top: 1rem;
        }
        .update-time {
            background: #E8F5E9;
            padding: 5px 15px;
            border-radius: 20px;
            font-weight: 600;
            color: var(--primary-green);
        }
        h2 {
            color: var(--dark-brown);
            font-size: 2rem;
            margin: 2.5rem 0 1.2rem;
            padding-bottom: 10px;
            border-bottom: 2px dashed var(--light-brown);
        }
        h3 {
            color: var(--primary-green);
            font-size: 1.6rem;
            margin: 2rem 0 1rem;
        }
        h4 {
            color: var(--text-dark);
            font-size: 1.3rem;
            margin: 1.5rem 0 0.8rem;
        }
        p {
            margin-bottom: 1.5rem;
            text-align: justify;
            font-size: 1.1rem;
        }
        .highlight-box {
            background: linear-gradient(to right, #E8F5E9, #F1F8E9);
            border-left: 5px solid var(--primary-green);
            padding: 1.5rem;
            margin: 2rem 0;
            border-radius: 0 10px 10px 0;
        }
        .feature-img {
            width: 100%;
            max-height: 500px;
            object-fit: cover;
            border-radius: 10px;
            margin: 2rem 0;
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
            transition: transform 0.5s ease;
        }
        .feature-img:hover {
            transform: scale(1.01);
        }
        .internal-links {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            gap: 1rem;
            margin: 2.5rem 0;
        }
        .internal-link {
            background: var(--white);
            border: 2px solid var(--light-brown);
            border-radius: 10px;
            padding: 1.2rem;
            text-decoration: none;
            color: var(--text-dark);
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .internal-link:hover {
            border-color: var(--primary-green);
            transform: translateY(-5px);
            box-shadow: 0 10px 20px var(--shadow);
        }
        .internal-link i {
            color: var(--primary-green);
            font-size: 1.5rem;
        }
        aside {
            display: flex;
            flex-direction: column;
            gap: 2rem;
        }
        .sidebar-box {
            background: var(--white);
            padding: 1.8rem;
            border-radius: 15px;
            box-shadow: 0 5px 15px var(--shadow);
        }
        .sidebar-box h3 {
            font-size: 1.4rem;
            margin-top: 0;
            color: var(--dark-brown);
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .sidebar-box h3 i {
            color: var(--primary-green);
        }
        .rating-form, .comment-form {
            display: flex;
            flex-direction: column;
            gap: 1.2rem;
        }
        .stars {
            display: flex;
            justify-content: center;
            gap: 10px;
            font-size: 2rem;
            cursor: pointer;
            margin: 10px 0;
        }
        .star {
            color: var(--light-brown);
            transition: color 0.2s;
        }
        .star:hover,
        .star.active {
            color: var(--accent-yellow);
        }
        .form-group {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        .form-group label {
            font-weight: 600;
            color: var(--text-dark);
        }
        .form-group input,
        .form-group textarea,
        .form-group select {
            padding: 12px 15px;
            border: 2px solid var(--light-brown);
            border-radius: 8px;
            font-family: inherit;
            font-size: 1rem;
            transition: border 0.3s;
        }
        .form-group input:focus,
        .form-group textarea:focus,
        .form-group select:focus {
            outline: none;
            border-color: var(--primary-green);
        }
        .btn {
            background: linear-gradient(to right, var(--primary-green), var(--secondary-green));
            color: var(--white);
            border: none;
            padding: 14px 25px;
            border-radius: 8px;
            font-weight: 700;
            font-size: 1.1rem;
            cursor: pointer;
            transition: all 0.3s ease;
            text-align: center;
            text-decoration: none;
        }
        .btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 7px 15px rgba(76, 175, 80, 0.4);
        }
        footer {
            background: var(--dark-brown);
            color: var(--white);
            padding: 3rem 0 1.5rem;
            margin-top: 3rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2.5rem;
            margin-bottom: 2.5rem;
        }
        .footer-section h3 {
            color: var(--accent-yellow);
            font-size: 1.5rem;
            margin-bottom: 1.5rem;
        }
        friend-link {
            display: block;
            margin-bottom: 1rem;
        }
        friend-link a {
            color: var(--light-brown);
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 10px;
            transition: color 0.3s;
        }
        friend-link a:hover {
            color: var(--white);
            text-decoration: underline;
        }
        .copyright {
            text-align: center;
            padding-top: 1.5rem;
            border-top: 1px solid rgba(255,255,255,0.1);
            font-size: 0.9rem;
            color: var(--light-brown);
        }
        @media (max-width: 768px) {
            .header-top {
                flex-direction: column;
                align-items: flex-start;
                gap: 1rem;
            }
            .search-form {
                width: 100%;
            }
            .mobile-toggle {
                display: block;
                position: absolute;
                top: 20px;
                right: 20px;
            }
            nav {
                display: none;
                margin-top: 1rem;
            }
            nav.active {
                display: block;
            }
            .nav-list {
                flex-direction: column;
            }
            h1 {
                font-size: 2.2rem;
            }
            .article-content {
                padding: 1.5rem;
            }
            .internal-links {
                grid-template-columns: 1fr;
            }
        }
        .emoji {
            font-size: 1.2em;
            margin-right: 5px;
        }
        .key-term {
            background: linear-gradient(120deg, var(--accent-yellow) 0%, var(--accent-yellow) 100%);
            background-repeat: no-repeat;
            background-size: 100% 0.3em;
            background-position: 0 90%;
            font-weight: 700;
            color: var(--text-dark);
            padding: 0 2px;
        }
        .stat-box {
            display: inline-block;
            background: var(--primary-green);
            color: var(--white);
            padding: 5px 12px;
            border-radius: 20px;
            font-weight: bold;
            margin: 0 5px;
            font-size: 0.9em;
        }