/* 全局样式 */
    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
    }

    body {
        font-family: 'Roboto', sans-serif;
        color: #333;
        background: linear-gradient(135deg, #1e3c72, #2a5298);
        min-height: 100vh;
        display: flex;
        flex-direction: column;
    }

    a {
        color: #ff9800;
        text-decoration: none;
        transition: color 0.3s ease;
    }

    a:hover {
        color: #e65100;
    }

    /* 导航栏 */
    .navbar {
        display: flex;
        justify-content: space-between;
        align-items: center;
        background: rgba(255, 255, 255, 0.8);
        padding: 15px 30px;
        position: sticky;
        top: 0;
        z-index: 1000;
        backdrop-filter: blur(10px);
        box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    }

    .navbar .logo {
        font-family: 'Poppins', sans-serif;
        font-size: 1.5rem;
        font-weight: bold;
        color: #1e3c72;
    }

    .navbar .nav-links {
        display: flex;
        gap: 20px;
    }

    .navbar .nav-links a {
        font-family: 'Poppins', sans-serif;
        font-size: 1rem;
        font-weight: 500;
        color: #1e3c72;
    }

    /* 头部横幅 */
    .hero {
        flex: 1;
        display: flex;
        align-items: center;
        justify-content: center;
        background: radial-gradient(circle, rgba(255, 87, 34, 0.3), transparent);
        animation: aurora-move 15s linear infinite;
        padding: 50px 20px;
    }

    .hero-content {
        text-align: center;
        color: #fff;
    }

    .hero-content h1 {
        font-family: 'Poppins', sans-serif;
        font-size: 3rem;
        margin-bottom: 20px;
    }

    .hero-content p {
        font-size: 1.2rem;
        margin-bottom: 30px;
    }

    .hero-content .cta-button {
        padding: 15px 30px;
        background: #ff9800;
        color: #fff;
        border: none;
        border-radius: 25px;
        font-size: 1rem;
        cursor: pointer;
        transition: background 0.3s ease;
    }

    .hero-content .cta-button:hover {
        background: #e65100;
    }

    /* 主要内容区 */
    .main {
        flex: 3;
        padding: 40px 20px;
        background: #f5f5f5;
    }

    .section {
        margin-bottom: 60px;
    }

    .section h2 {
        font-family: 'Poppins', sans-serif;
        font-size: 2rem;
        color: #1e3c72;
        margin-bottom: 20px;
        text-align: center;
    }

    .cards-container {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 20px;
    }

    .card {
        background: linear-gradient(135deg, #e8f0fe, #d3e4fd);
        border-radius: 15px;
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        overflow: hidden;
        transition: transform 0.3s ease, box-shadow 0.3s ease;
    }

    .card:hover {
        transform: translateY(-10px);
        box-shadow: 0 10px 15px rgba(0,0,0,0.2);
    }

    .card img {
        width: 100%;
        height: 150px;
        object-fit: cover;
    }

    .card-content {
        padding: 20px;
    }

    .card-content h3 {
        font-family: 'Poppins', sans-serif;
        font-size: 1.5rem;
        margin-bottom: 10px;
        color: #1e3c72;
    }

    .card-content p {
        font-size: 1rem;
        margin-bottom: 15px;
        line-height: 1.6;
    }

    .card-content .progress {
        background: #ddd;
        border-radius: 10px;
        overflow: hidden;
        height: 10px;
    }

    .card-content .progress-bar {
        width: 70%;
        height: 100%;
        background: #ff9800;
        transition: width 0.3s ease;
    }

    /* 示例展示 */
    .example-display {
        background: #fff;
        padding: 30px;
        border-radius: 15px;
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        overflow: auto;
    }

    .example-display h2 {
        font-family: 'Poppins', sans-serif;
        font-size: 1.8rem;
        color: #1e3c72;
        margin-bottom: 15px;
    }

    .example-display article {
        font-size: 1rem;
        line-height: 1.8;
    }

    .example-display pre {
        background: #f0f0f0;
        padding: 15px;
        border-radius: 10px;
        overflow: auto;
        margin-bottom: 15px;
    }

    .example-display code {
        font-family: 'Courier New', monospace;
        color: #d63384;
    }

    /* 脚注 */
    .footer {
        background: rgba(255, 255, 255, 0.8);
        padding: 20px;
        text-align: center;
        font-size: 0.9rem;
        color: #555;
        backdrop-filter: blur(10px);
    }

    /* 动画 */
    @keyframes aurora-move {
        0% {
            background: radial-gradient(circle, rgba(255, 87, 34, 0.3), transparent);
        }
        50% {
            background: radial-gradient(circle, rgba(34, 193, 195, 0.3), transparent);
        }
        100% {
            background: radial-gradient(circle, rgba(255, 87, 34, 0.3), transparent);
        }
    }

    /* 响应式设计 */
    @media (max-width: 1440px) {
        .hero-content h1 {
            font-size: 2.5rem;
        }

        .navbar {
            padding: 10px 20px;
        }
    }

    @media (max-width: 1200px) {
        .navbar .nav-links a {
            font-size: 0.95rem;
        }

        .hero-content h1 {
            font-size: 2.2rem;
        }

        .card-content h3 {
            font-size: 1.3rem;
        }
    }

    @media (max-width: 1024px) {
        .hero-content h1 {
            font-size: 2rem;
        }

        .card-content h3 {
            font-size: 1.2rem;
        }
    }

    @media (max-width: 768px) {
        .navbar .nav-links {
            display: none;
        }

        .hero-content h1 {
            font-size: 1.8rem;
        }

        .card-content h3 {
            font-size: 1.1rem;
        }
    }

    @media (max-width: 480px) {
        .hero-content h1 {
            font-size: 1.5rem;
        }

        .card-content p, .example-display article {
            font-size: 0.9rem;
        }
    }

    @media (max-width: 320px) {
        .hero-content h1 {
            font-size: 1.2rem;
        }

        .card-content h3 {
            font-size: 1rem;
        }

        .card-content p, .example-display article {
            font-size: 0.8rem;
        }
    }