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

    body {
        font-family: 'Times New Roman', serif;
        background: linear-gradient(135deg, #000066, #4B0082, #FFA500);
        color: #FFFFFF;
        line-height: 1.6;
        overflow-x: hidden;
    }

    h1, h2, h3, h4 {
        font-family: 'Roboto', sans-serif;
        color: #FFFFFF;
    }

    h1 {
        font-size: 3em;
        text-align: center;
        margin: 20px 0;
    }

    h2 {
        font-size: 2em;
        margin: 20px 0;
    }

    h3 {
        font-size: 1.5em;
        margin: 15px 0;
    }

    h4 {
        font-size: 1.2em;
        margin: 10px 0;
    }

    p {
        font-size: 1em;
        margin: 10px 0;
    }

    nav {
        position: fixed;
        top: 0;
        width: 100%;
        background: rgba(0, 0, 0, 0.7);
        padding: 10px 0;
        z-index: 1000;
    }

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

    nav ul li {
        margin: 0 15px;
    }

    nav ul li a {
        text-decoration: none;
        color: #FFA500;
        font-size: 1.1em;
        transition: color 0.3s;
    }

    nav ul li a:hover {
        color: #FFFFFF;
    }

    .progress-bar {
        position: fixed;
        top: 0;
        left: 0;
        height: 5px;
        background: #FFA500;
        width: 0%;
        z-index: 1001;
        transition: width 0.25s;
    }

    .section {
        min-height: 100vh;
        padding: 100px 20px 50px 20px;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        text-align: center;
        background: transparent;
    }

    .section:nth-child(odd) {
        background: rgba(0, 0, 102, 0.8);
    }

    .section:nth-child(even) {
        background: rgba(75, 0, 130, 0.8);
    }

    .section img {
        max-width: 100%;
        height: auto;
        margin: 20px 0;
    }

    pre {
        background: rgba(255, 165, 0, 0.2);
        padding: 15px;
        border-radius: 5px;
        overflow-x: auto;
        margin: 20px 0;
    }

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

    table {
        width: 100%;
        border-collapse: collapse;
        margin: 20px 0;
    }

    table, th, td {
        border: 1px solid #FFA500;
    }

    th, td {
        padding: 10px;
        text-align: center;
    }

    th {
        background: rgba(255, 165, 0, 0.5);
    }

    /* 响应式设计 */
    @media (max-width: 1440px) {
        h1 {
            font-size: 2.5em;
        }
        h2 {
            font-size: 1.8em;
        }
    }

    @media (max-width: 1200px) {
        nav ul {
            flex-direction: column;
        }
        nav ul li {
            margin: 10px 0;
        }
    }

    @media (max-width: 1024px) {
        h1 {
            font-size: 2em;
        }
        h2 {
            font-size: 1.5em;
        }
    }

    @media (max-width: 768px) {
        h1 {
            font-size: 1.8em;
        }
        h2 {
            font-size: 1.3em;
        }
    }

    @media (max-width: 480px) {
        nav ul {
            flex-direction: column;
        }
        nav ul li {
            margin: 5px 0;
        }
        h1 {
            font-size: 1.5em;
        }
        h2 {
            font-size: 1.2em;
        }
        p {
            font-size: 0.9em;
        }
    }

    @media (max-width: 320px) {
        h1 {
            font-size: 1.2em;
        }
        h2 {
            font-size: 1em;
        }
        p {
            font-size: 0.8em;
        }
    }

    /* 提示信息样式 */
    .reference-note {
        position: fixed;
        bottom: 10px;
        right: 10px;
        background: rgba(0, 0, 0, 0.7);
        padding: 5px 10px;
        border-radius: 5px;
        font-size: 0.9em;
        color: #FFA500;
    }

    /* 动画效果 */
    .fade-in {
        animation: fadeIn 2s ease-in-out;
    }

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