/* 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 */
    background: linear-gradient(135deg, #e0f7fa 25%, #fffde7 75%); /* 渐变背景，主色70% */
    color: #333;
    line-height: 1.6;
}

/* 导航栏样式 */
.navbar {
    display: flex;
    justify-content: space-around;
    align-items: center;
    background-color: #00796b; /* 辅色25% */
    padding: 20px;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.navbar a {
    color: #ffffff;
    text-decoration: none;
    font-size: 18px;
    transition: color 0.3s ease;
}

.navbar a:hover {
    color: #ffab00; /* 点缀色5% */
}

/* 主内容区域 */
.container {
    display: grid;
    grid-template-columns: 1fr 3fr;
    gap: 20px;
    padding: 100px 50px 50px 50px; /* 顶部留出导航栏空间 */
}

/* 侧边导航 */
.sidebar {
    background-color: #004d40; /* 辅色25% */
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.sidebar a {
    display: block;
    color: #ffffff;
    text-decoration: none;
    margin: 10px 0;
    font-size: 16px;
    transition: color 0.3s ease;
}

.sidebar a:hover {
    color: #ffab00; /* 点缀色5% */
}

/* 文章内容 */
.content {
    background-color: #ffffff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

/* 章节导航 */
.chapter-nav {
    position: fixed;
    top: 100px;
    right: 20px;
    background-color: rgba(0,0,0,0.05);
    padding: 10px;
    border-radius: 8px;
}

.chapter-nav a {
    display: block;
    color: #00796b;
    text-decoration: none;
    margin: 5px 0;
    font-size: 14px;
    transition: color 0.3s ease;
}

.chapter-nav a:hover {
    color: #ffab00; /* 点缀色5% */
}

/* 图片样式 */
img.decorative {
    width: 100%;
    border-radius: 12px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

img.decorative:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 16px rgba(0,0,0,0.3);
}

/* 代码块样式 */
pre {
    background: #f5f5f5;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    font-size: 14px;
    line-height: 1.5;
    border-left: 4px solid #ffab00; /* 点缀色5% */
}

code {
    font-family: 'Courier New', Courier, monospace;
    color: #d84315;
}

/* 按钮样式 */
.button {
    background-color: #00796b; /* 辅色25% */
    color: #ffffff;
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
    text-decoration: none;
    display: inline-block;
    margin: 10px 0;
}

.button:hover {
    background-color: #ffab00; /* 点缀色5% */
    transform: scale(1.05);
}

/* 折叠内容样式 */
.collapsible {
    background-color: #e0f7fa;
    color: #00796b;
    cursor: pointer;
    padding: 10px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 16px;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.collapsible:hover {
    background-color: #b2ebf2;
}

.collapsible:after {
    content: '\002B'; /* 加号 */
    float: right;
}

.collapsible.active:after {
    content: '\2212'; /* 减号 */
}

.content-collapsible {
    padding: 0 15px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    background-color: #ffffff;
    border-left: 4px solid #ffab00; /* 点缀色5% */
}

/* 提示语样式 */
.prompt {
    background-color: #ffeb3b; /* 主色70%中的一部分 */
    padding: 15px;
    border-radius: 8px;
    text-align: center;
    font-size: 18px;
    margin: 20px 0;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .container {
        grid-template-columns: 1fr;
        padding: 100px 20px 20px 20px;
    }
    
    .chapter-nav {
        display: none;
    }
}

@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
    }
    
    .navbar a {
        margin: 10px 0;
        font-size: 16px;
    }
    
    .sidebar {
        display: none;
    }
}

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.section {
    animation: fadeIn 1s ease forwards;
    opacity: 0;
}

.section.visible {
    opacity: 1;
}