/* 全局样式设置 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif; /* 无衬线字体，提升现代感与可读性 */
    background: linear-gradient(135deg, #F5F5F5 70%, #FFFFFF 30%); /* 主色调与辅色调的渐变背景 */
    color: #333333; /* 主要文字颜色，保证良好对比 */
    line-height: 1.6;
}

/* 导航栏样式 */
.navbar {
    background: linear-gradient(90deg, #2196F3, #64B5F6); /* 渐变背景色，传递信任感与科技感 */
    padding: 20px;
    position: fixed;
    width: 100%;
    top: 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1); /* 阴影效果，增强立体感 */
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar a {
    color: #FFFFFF;
    text-decoration: none;
    margin: 0 15px;
    font-size: 16px;
    transition: color 0.3s ease;
}

.navbar a:hover {
    color: #FF9800; /* 强调色，用于悬停效果，吸引注意力 */
}

.navbar .logo {
    font-size: 20px;
    font-weight: bold;
}

/* 主内容区域样式 */
.container {
    display: flex;
    flex-direction: column;
    padding: 100px 20px 20px 20px; /* 上方留出导航栏空间 */
    max-width: 1200px;
    margin: 0 auto;
}

h2, h3, h4 {
    color: #2196F3; /* 标题颜色，与主色调一致 */
}

h2 {
    font-size: 24px;
    margin-bottom: 20px;
}

h3 {
    font-size: 20px;
    margin-top: 30px;
    margin-bottom: 15px;
}

h4 {
    font-size: 18px;
    margin-top: 25px;
    margin-bottom: 10px;
}

p {
    font-size: 16px;
    margin-bottom: 15px;
}

pre {
    background: #F0F0F0;
    padding: 15px;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 20px;
}

pre code {
    font-family: 'Courier New', Courier, monospace;
    color: #333333;
}

/* 图片样式 */
img {
    width: 100%;
    max-width: 320px;
    height: auto;
    border-radius: 10px; /* 圆角效果 */
    box-shadow: 0 4px 8px rgba(0,0,0,0.1); /* 阴影效果 */
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    margin: 10px;
}

img:hover {
    transform: scale(1.05); /* 悬停时放大效果 */
    box-shadow: 0 8px 16px rgba(0,0,0,0.2); /* 增强阴影 */
}

/* 导航系统样式 */
.nav-chapters {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 30px;
}

.nav-chapters a {
    background-color: #FF9800;
    color: #FFFFFF;
    padding: 10px 15px;
    border-radius: 5px;
    text-decoration: none;
    font-size: 14px;
    transition: background-color 0.3s ease;
}

.nav-chapters a:hover {
    background-color: #FFB74D;
}

/* 响应式布局 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        align-items: flex-start;
    }

    .nav-chapters {
        flex-direction: column;
    }

    img {
        max-width: 100%;
    }
}

/* 按钮样式 */
.button {
    background-color: #FF9800;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    transition: background-color 0.3s ease, transform 0.3s ease;
    cursor: pointer;
    font-size: 16px;
}

.button:hover {
    background-color: #FFB74D;
    transform: translateY(-2px);
}

/* 代码示例样式 */
.code-example {
    background-color: #2D2D2D;
    color: #CCCCCC;
    padding: 20px;
    border-radius: 5px;
    overflow-x: auto;
    font-family: 'Courier New', Courier, monospace;
    margin-bottom: 20px;
}

.code-example code {
    display: block;
    white-space: pre;
}

/* 折叠区域样式 */
.collapsible {
    background-color: #2196F3;
    color: white;
    cursor: pointer;
    padding: 10px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 16px;
    border-radius: 5px;
    margin-bottom: 10px;
}

.collapsible:hover {
    background-color: #64B5F6;
}

.collapsible-content {
    padding: 0 15px;
    display: none;
    overflow: hidden;
    background-color: #f1f1f1;
    border-radius: 5px;
    margin-bottom: 15px;
}

.collapsible-content p {
    margin: 10px 0;
}

/* 提示语样式 */
.notice {
    background-color: #FFEB3B;
    color: #333333;
    padding: 15px;
    border-left: 5px solid #FF9800;
    margin: 20px 0;
    font-size: 16px;
}

/* 页脚样式 */
.footer {
    background-color: #2196F3;
    color: #FFFFFF;
    text-align: center;
    padding: 20px;
    margin-top: 40px;
}

.footer a {
    color: #FFFFFF;
    text-decoration: none;
    margin: 0 10px;
}

.footer a:hover {
    text-decoration: underline;
}

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

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