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

    /* 全局字体与背景 */
    body {
        font-family: 'Roboto', sans-serif;
        background: linear-gradient(135deg, #A8E6CF, #DCEDC1, #FFD3B6, #FFAAA5);
        color: #333;
        line-height: 1.6;
        padding: 20px;
        animation: background-animation 30s ease infinite;
    }

    @keyframes background-animation {
        0% { background-position: 0% 50%; }
        50% { background-position: 100% 50%; }
        100% { background-position: 0% 50%; }
    }

    /* 头部样式 */
    header {
        background: rgba(255, 255, 255, 0.8);
        padding: 30px;
        border-radius: 15px;
        text-align: center;
        box-shadow: 0 8px 16px rgba(0,0,0,0.2);
        margin-bottom: 40px;
    }

    header h1 {
        font-size: 3rem;
        color: #388E3C;
        margin-bottom: 10px;
        text-transform: uppercase;
        letter-spacing: 2px;
    }

    header p {
        font-size: 1.2rem;
        color: #555;
    }

    /* 导航菜单 */
    nav {
        margin-top: 20px;
    }

    nav ul {
        list-style: none;
        display: flex;
        justify-content: center;
        flex-wrap: wrap;
    }

    nav ul li {
        margin: 0 20px;
    }

    nav ul li a {
        text-decoration: none;
        color: #FF7043;
        font-weight: bold;
        font-size: 1.1rem;
        transition: color 0.3s, transform 0.3s;
    }

    nav ul li a:hover {
        color: #BF360C;
        transform: scale(1.1);
    }

    /* 主容器 */
    .container {
        max-width: 1200px;
        margin: 0 auto;
        background: rgba(255, 255, 255, 0.95);
        padding: 40px;
        border-radius: 20px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    }

    /* 段落与标题 */
    h2, h3, h4 {
        color: #2E7D32;
        margin-bottom: 20px;
    }

    h2 {
        font-size: 2.5rem;
        text-align: center;
    }

    h3 {
        font-size: 2rem;
        margin-top: 30px;
    }

    p {
        font-size: 1.1rem;
        margin-bottom: 15px;
        color: #444;
    }

    /* 图文混排 */
    .image-grid {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 20px;
        margin-top: 30px;
    }

    .image-grid img {
        width: 100%;
        border-radius: 10px;
        transition: transform 0.3s, box-shadow 0.3s;
    }

    .image-grid img:hover {
        transform: scale(1.05);
        box-shadow: 0 8px 16px rgba(0,0,0,0.2);
    }

    /* 按钮样式 */
    .btn {
        display: inline-block;
        padding: 12px 25px;
        background: #FF7043;
        color: #fff;
        border: none;
        border-radius: 30px;
        cursor: pointer;
        text-decoration: none;
        font-size: 1rem;
        transition: background 0.3s, transform 0.3s;
        margin-top: 20px;
    }

    .btn:hover {
        background: #BF360C;
        transform: translateY(-3px);
    }

    /* 代码块样式 */
    pre {
        background: #F5F5F5;
        padding: 20px;
        border-radius: 10px;
        overflow-x: auto;
        font-family: 'Courier New', Courier, monospace;
        margin-bottom: 20px;
    }

    code {
        color: #D84315;
        font-size: 1rem;
    }

    /* 卡片样式 */
    .card {
        background: #fff;
        border-radius: 15px;
        padding: 25px;
        box-shadow: 0 6px 12px rgba(0,0,0,0.1);
        transition: transform 0.3s, box-shadow 0.3s;
    }

    .card:hover {
        transform: translateY(-5px);
        box-shadow: 0 12px 24px rgba(0,0,0,0.2);
    }

    /* 表格样式 */
    table {
        width: 100%;
        border-collapse: collapse;
        margin: 30px 0;
    }

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

    th, td {
        padding: 15px;
        text-align: left;
    }

    th {
        background-color: #f0f0f0;
        color: #333;
    }

    /* 页脚样式 */
    footer {
        text-align: center;
        padding: 30px;
        background: rgba(255, 255, 255, 0.8);
        border-radius: 15px;
        box-shadow: 0 -6px 12px rgba(0,0,0,0.1);
        margin-top: 40px;
    }

    footer p {
        color: #757575;
        font-size: 1rem;
    }

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

    .background-animated {
        background: radial-gradient(circle, rgb(255, 87, 34), transparent);
        animation: aurora-move 15s linear infinite;
    }

    /* 响应式设计 */
    @media (max-width: 1440px) {
        .container {
            padding: 35px;
        }

        header h1 {
            font-size: 2.8rem;
        }

        h2 {
            font-size: 2.3rem;
        }

        h3 {
            font-size: 1.8rem;
        }
    }

    @media (max-width: 1200px) {
        .image-grid {
            grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        }

        nav ul li {
            margin: 0 15px;
        }
    }

    @media (max-width: 1024px) {
        nav ul {
            flex-direction: column;
        }

        nav ul li {
            margin: 10px 0;
        }

        h2 {
            font-size: 2rem;
        }

        h3 {
            font-size: 1.6rem;
        }
    }

    @media (max-width: 768px) {
        body {
            padding: 15px;
        }

        header h1 {
            font-size: 2.5rem;
        }

        nav ul {
            flex-direction: column;
        }

        nav ul li {
            margin: 8px 0;
        }

        .image-grid {
            grid-template-columns: 1fr;
        }

        h2 {
            font-size: 1.8rem;
        }

        h3 {
            font-size: 1.4rem;
        }
    }

    @media (max-width: 480px) {
        body {
            padding: 10px;
        }

        header h1 {
            font-size: 2rem;
        }

        nav ul li a {
            font-size: 0.9rem;
        }

        h2 {
            font-size: 1.6rem;
        }

        h3 {
            font-size: 1.2rem;
        }
    }

    @media (max-width: 320px) {
        header h1 {
            font-size: 1.8rem;
        }

        nav ul li a {
            font-size: 0.8rem;
        }

        h2 {
            font-size: 1.4rem;
        }

        h3 {
            font-size: 1rem;
        }
    }

    /* 图标动画 */
    .icon {
        transition: transform 0.3s ease, opacity 0.3s ease;
    }

    .icon:hover {
        transform: rotate(10deg);
        opacity: 0.8;
    }

    /* 无障碍设计 */
    a[aria-label] {
        position: relative;
    }

    a[aria-label]:focus::after {
        content: attr(aria-label);
        position: absolute;
        left: 0;
        bottom: -20px;
        background: #000;
        color: #fff;
        padding: 3px 8px;
        border-radius: 4px;
        font-size: 0.8rem;
    }