/* 全局样式设置 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif; /* 使用现代无衬线字体 */
    font-size: 16px; /* 正文字号设置为16px */
    line-height: 1.6;
    background: linear-gradient(135deg, #0d47a1, #cfd8dc); /* 线性渐变背景 */
    color: #333333;
}

/* 导航栏样式 */
.navbar {
    position: fixed; /* 固定在顶部 */
    top: 0;
    width: 100%;
    background-color: rgba(13, 71, 161, 0.9); /* 半透明深蓝色背景 */
    color: #ffffff;
    padding: 15px 30px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1); /* 阴影效果 */
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar .logo {
    font-size: 1.5em;
    font-weight: bold;
}

.navbar ul {
    list-style: none;
    display: flex;
    margin: 0;
    padding: 0;
}

.navbar ul li {
    position: relative;
    margin-left: 20px;
}

.navbar ul li a {
    color: #ffffff;
    text-decoration: none;
    transition: color 0.3s ease;
}

.navbar ul li a:hover {
    color: #ff9800; /* 亮橙色悬停效果 */
}

.navbar ul li .dropdown {
    display: none; /* 隐藏下拉菜单 */
    position: absolute;
    top: 35px;
    left: 0;
    background-color: #0d47a1;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.navbar ul li:hover .dropdown {
    display: block; /* 鼠标悬停显示下拉菜单 */
}

.navbar ul li .dropdown li {
    margin: 10px 0;
}

.navbar .search-bar {
    position: relative;
}

.navbar .search-bar input {
    padding: 5px 10px;
    border: none;
    border-radius: 4px;
}

.navbar .search-bar button {
    position: absolute;
    right: 0;
    top: 0;
    bottom: 0;
    background-color: #ff9800;
    border: none;
    color: #ffffff;
    padding: 0 10px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.navbar .search-bar button:hover {
    background-color: #e68900;
}

/* 主容器样式 */
.container {
    max-width: 1200px;
    margin: 100px auto 50px; /* 顶部留出导航栏空间 */
    padding: 20px;
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

/* 信息提示样式 */
.reference-note {
    width: 100%;
    background-color: rgba(255, 152, 0, 0.1);
    border-left: 5px solid #ff9800;
    padding: 10px 20px;
    margin-bottom: 20px;
    font-size: 1.2em;
}

/* 章节导航样式 */
.chapter-nav {
    position: fixed;
    top: 100px;
    right: 20px;
    width: 200px;
    background-color: rgba(12, 33, 61, 0.8);
    padding: 15px;
    border-radius: 8px;
}

.chapter-nav h3 {
    color: #ffffff;
    margin-bottom: 10px;
}

.chapter-nav ul {
    list-style: none;
    padding: 0;
}

.chapter-nav ul li a {
    color: #ffffff;
    text-decoration: none;
    display: block;
    padding: 5px 0;
    transition: color 0.3s ease;
}

.chapter-nav ul li a:hover {
    color: #ff9800;
}

/* 文章内容样式 */
article {
    flex: 3;
    background-color: rgba(255, 255, 255, 0.9);
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

article h2, article h3, article h4 {
    color: #0d47a1;
}

article h2 {
    font-size: 1.8em;
    margin-top: 20px;
}

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

article p, article section {
    font-size: 1em;
    margin-bottom: 15px;
}

article pre {
    background-color: #f5f5f5;
    padding: 10px;
    border-radius: 4px;
    overflow-x: auto;
}

/* 图片样式 */
.image-gallery {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.image-gallery img {
    width: 100%;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.image-gallery img:hover {
    transform: scale(1.05);
}

/* 卡片式设计 */
.card {
    background-color: #ffffff;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: 20px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 6px 8px rgba(0, 0, 0, 0.15);
}

/* 按钮样式 */
.button {
    background-color: #ff9800;
    color: #ffffff;
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.button:hover {
    background-color: #e68900;
    transform: scale(1.05);
}

/* 仪表盘样式 */
.dashboard {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.dashboard-item {
    background-color: #f5f5f5;
    border-radius: 8px;
    padding: 15px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        flex-direction: column;
        padding: 10px;
    }
    .chapter-nav {
        display: none; /* 移动端隐藏章节导航 */
    }
}

@media (max-width: 480px) {
    .button {
        padding: 15px 25px;
        font-size: 16px;
    }
    .navbar {
        padding: 10px 20px;
    }
}