/* 全局样式 - 卡通可爱风格 */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: "Microsoft YaHei", 幼圆, sans-serif;
        }

        body {
            background-color: #f0f8f0;
            color: #333;
            background-image: url("data:image/svg+xml,%3Csvg width='100' height='100' viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M11 18c3.866 0 7-3.134 7-7s-3.134-7-7-7-7 3.134-7 7 3.134 7 7 7zm48 25c3.866 0 7-3.134 7-7s-3.134-7-7-7-7 3.134-7 7 3.134 7 7 7zm-43-7c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zm63 31c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zM34 90c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zm56-76c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zM12 86c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm28-65c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm23-11c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm-6 60c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm29 22c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zM32 63c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm57-13c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm-9-21c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM60 91c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM35 41c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM12 60c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2z' fill='%234CAF50' fill-opacity='0.2' fill-rule='evenodd'/%3E%3C/svg%3E");
        }

        /* 头部样式 */
        header {
            background: linear-gradient(120deg, #4CAF50 0%, #66BB6A 100%);
            padding: 30px 20px;
            text-align: center;
            border-radius: 0 0 30px 30px;
            box-shadow: 0 6px 15px rgba(0,0,0,0.1);
            margin-bottom: 40px;
        }

        .header-logo {
            font-size: 2.5rem;
            color: #fff;
            text-shadow: 3px 3px 6px rgba(0,0,0,0.2);
            margin-bottom: 10px;
        }

        .header-title {
            color: #fff;
            font-size: 1.8rem;
            margin-bottom: 15px;
            font-weight: normal;
        }

        .header-subtitle {
            color: #f1f8e9;
            font-size: 1.1rem;
        }

        /* 主容器 */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        /* 知识点导航模块 */
        .nav-module {
            background: white;
            border-radius: 25px;
            padding: 30px;
            margin-bottom: 40px;
            box-shadow: 0 8px 20px rgba(0,0,0,0.08);
            border: 3px solid #c8e6c9;
        }

        .module-title {
            color: #388e3c;
            font-size: 2rem;
            text-align: center;
            margin-bottom: 30px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 15px;
        }

        .module-title::before,
        .module-title::after {
            content: "✨";
            font-size: 1.8rem;
        }

        /* 链接网格布局 */
        .link-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 20px;
        }

        /* 链接样式 */
        .link-item {
            background: linear-gradient(180deg, #f1f8e9 0%, #dcedc8 100%);
            border-radius: 20px;
            padding: 20px;
            text-align: center;
            transition: all 0.3s ease;
            box-shadow: 0 4px 10px rgba(76,175,80,0.1);
            border: 2px solid #aed581;
        }

        .link-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 15px rgba(76,175,80,0.2);
            border-color: #4CAF50;
        }

        .link-item a {
            text-decoration: none;
            color: #388e3c;
            font-size: 1.2rem;
            font-weight: 600;
            display: block;
            transition: all 0.3s ease;
        }

        .link-item a:hover {
            color: #2e7d32;
            font-size: 1.25rem;
        }

        .link-icon {
            font-size: 2rem;
            margin-bottom: 10px;
            display: block;
        }

        /* 底部样式 */
        footer {
            background: #f1f8e9;
            padding: 20px;
            text-align: center;
            border-radius: 30px 30px 0 0;
            margin-top: 50px;
            border-top: 3px solid #aed581;
        }

        .footer-text {
            color: #388e3c;
            font-size: 1rem;
            line-height: 1.8;
        }

        /* 响应式适配 */
        @media (max-width: 900px) {
            .link-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .header-logo {
                font-size: 2rem;
            }
            .module-title {
                font-size: 1.8rem;
            }
        }

        @media (max-width: 600px) {
            .link-grid {
                grid-template-columns: 1fr;
            }
            .header-logo {
                font-size: 1.8rem;
            }
            .header-title {
                font-size: 1.5rem;
            }
            .nav-module {
                padding: 20px 15px;
            }
            .link-item a {
                font-size: 1.1rem;
            }
        }
		 footer {
            max-width: 1200px;
            margin: 0 auto 30px;
            padding: 20px;
            text-align: center;
            border-top: 2px solid #d6f5d4;
            background: #f8fef8;
            border-radius: 15px;
        }

        .footer-links {
            margin-bottom: 15px;
            display: flex;
            justify-content: center;
            gap: 25px;
            flex-wrap: wrap;
        }

        .footer-links a {
            color: #4ebb4e;
            text-decoration: none;
            font-size: 1rem;
            transition: all 0.3s ease;
        }

        .footer-links a:hover {
            color: #ff9a9e;
            text-decoration: underline;
        }

        .copyright {
            color: #666;
            font-size: 0.9rem;
        }