/* 全局样式 */
    body {
        font-family: 'Roboto', sans-serif;
        color: #333;
        background: radial-gradient(circle, rgba(30, 144, 255, 0.8), transparent);
        margin: 0;
        padding: 0;
    }

    header {
        background: #1E90FF;
        color: white;
        padding: 1rem 2rem;
        position: fixed;
        width: 100%;
        top: 0;
        z-index: 1000;
        box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    }

    nav ul {
        list-style: none;
        display: flex;
        justify-content: space-around;
        align-items: center;
        margin: 0;
        padding: 0;
    }

    nav ul li a {
        color: white;
        text-decoration: none;
        font-weight: bold;
        padding: 0.5rem 1rem;
        transition: background 0.3s;
    }

    nav ul li a:hover {
        background: rgba(255, 215, 0, 0.3);
        border-radius: 4px;
    }

    .container {
        padding: 6rem 2rem 2rem 2rem;
        max-width: 1200px;
        margin: 0 auto;
    }

    h1, h2, h3, h4 {
        color: #2E7D32;
    }

    .gradient-background {
        background: linear-gradient(135deg, #1E90FF, #8BC34A);
        padding: 2rem;
        border-radius: 8px;
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        margin-bottom: 2rem;
    }

    .card {
        background-color: white;
        border-radius: 8px;
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        padding: 1.5rem;
        margin-bottom: 1.5rem;
        transition: transform 0.3s ease, box-shadow 0.3s ease;
    }

    .card:hover {
        transform: translateY(-10px);
        box-shadow: 0 8px 12px rgba(0,0,0,0.2);
    }

    pre {
        background: #f5f5f5;
        padding: 1rem;
        border-radius: 4px;
        overflow-x: auto;
    }

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

    img {
        max-width: 100%;
        height: auto;
        border-radius: 8px;
        margin-bottom: 1rem;
    }

    table {
        width: 100%;
        border-collapse: collapse;
        margin-bottom: 1.5rem;
    }

    table, th, td {
        border: 1px solid #ddd;
    }

    th, td {
        padding: 0.75rem;
        text-align: left;
    }

    th {
        background-color: #f2f2f2;
    }

    .footer {
        background: #1E90FF;
        color: white;
        text-align: center;
        padding: 1rem 0;
        position: fixed;
        width: 100%;
        bottom: 0;
    }

    /* 动画效果 */
    @keyframes auroraMove {
        0% { background-position: 0% 50%; }
        50% { background-position: 100% 50%; }
        100% { background-position: 0% 50%; }
    }

    body {
        animation: auroraMove 15s linear infinite;
        background-size: 400% 400%;
    }

    @keyframes fadeIn {
        from { opacity: 0; }
        to { opacity: 1; }
    }

    .content {
        animation: fadeIn 1s ease-in-out;
    }

    /* 响应式设计 */
    @media (max-width: 320px) {
        nav ul {
            flex-direction: column;
        }
        .container {
            padding: 6rem 1rem 1rem 1rem;
        }
    }

    @media (max-width: 480px) {
        nav ul li a {
            padding: 0.5rem;
            font-size: 0.9rem;
        }
    }

    @media (max-width: 768px) {
        .container {
            padding: 6rem 1.5rem 1.5rem 1.5rem;
        }
        .card {
            padding: 1rem;
        }
    }

    @media (max-width: 1024px) {
        nav ul {
            justify-content: space-between;
        }
    }

    @media (min-width: 1200px) {
        .container {
            padding: 6rem 3rem 3rem 3rem;
        }
    }

    @media (min-width: 1440px) {
        .container {
            max-width: 1440px;
        }
    }