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

/* 设定页面背景色，避免使用白色，采用主色调深蓝色 */
body {
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #1A237E 70%, #FAFAFA 25%, #FFC107 5%);
    color: #333;
    line-height: 1.6;
    padding: 20px;
}

/* 顶部导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: #1A237E;
    display: flex;
    justify-content: space-around;
    align-items: center;
    padding: 15px 0;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* 导航链接样式 */
.navbar a {
    color: #FAFAFA;
    text-decoration: none;
    font-size: 16px;
    transition: color 0.3s ease;
}

.navbar a:hover {
    color: #FFC107;
}

/* 主内容区的容器，采用网格布局 */
.container {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 20px;
    max-width: 1200px;
    margin: 100px auto 50px auto; /* 上方留出导航栏空间 */
    padding: 20px;
}

/* 设置不同的内容块，占据不同的网格列 */
.content-block {
    grid-column: span 12;
    background-color: rgba(255, 255, 255, 0.8);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: relative;
}

/* 标题样式 */
.content-block h2, .content-block h3, .content-block h4 {
    color: #1A237E;
    margin-bottom: 15px;
}

.content-block h2 {
    font-size: 24px;
}

.content-block h3 {
    font-size: 20px;
}

.content-block h4 {
    font-size: 18px;
}

/* 段落样式 */
.content-block p {
    font-size: 16px;
    margin-bottom: 15px;
}

/* 代码块样式，与正文区分 */
.content-block pre {
    background-color: #f5f5f5;
    padding: 15px;
    border-radius: 5px;
    overflow-x: auto;
}

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

/* 表格样式 */
.content-block table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

.content-block table, .content-block th, .content-block td {
    border: 1px solid #ddd;
}

.content-block th, .content-block td {
    padding: 12px;
    text-align: left;
}

.content-block th {
    background-color: #1A237E;
    color: #FAFAFA;
}

/* 图片样式，添加圆角和阴影 */
.content-block img {
    width: 100%;
    max-width: 320px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

/* 渐变线条作为装饰元素 */
.decorative-line {
    height: 2px;
    background: linear-gradient(90deg, #1A237E, #FFC107);
    margin: 30px 0;
}

/* 响应式设计，适应不同屏幕宽度 */
@media (max-width: 768px) {
    .container {
        grid-template-columns: repeat(6, 1fr);
    }
}

@media (max-width: 480px) {
    .container {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 悬停效果，增加互动性 */
.button:hover {
    background-color: #FFC107;
    transform: scale(1.05);
    transition: all 0.3s ease;
}

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.fade-in {
    animation: fadeIn 2s ease-in;
}

/* 菜单项的悬停变色效果 */
.menu-item:hover {
    color: #FFC107;
}

/* 定位提示信息 */
.reference-note {
    position: absolute;
    top: -40px;
    left: 0;
    font-size: 14px;
    color: #FF5722;
}

/* 导航章节链接样式 */
.chapter-nav {
    position: fixed;
    right: 20px;
    top: 100px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.chapter-nav a {
    background-color: #FFC107;
    color: #1A237E;
    padding: 10px 15px;
    border-radius: 5px;
    text-decoration: none;
    font-size: 14px;
    transition: background-color 0.3s ease;
}

.chapter-nav a:hover {
    background-color: #FF9800;
}

/* 确保所有内部链接有 rel="nofollow" */
a[rel="nofollow"] {
    /* 无需额外样式 */
}

/* 确保代码块样式美观 */
.code-example {
    background-color: #272727;
    color: #f8f8f2;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    font-family: 'Courier New', Courier, monospace;
}

/* 留白和组块 */
.section {
    padding: 60px 20px;
    margin: 20px 0;
}

/* 按钮样式 */
.button {
    background-color: #4CAF50;
    color: #FAFAFA;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

.button:focus {
    outline: none;
}