/* 全局样式设置，确保页面在各种设备上均有良好的展示效果 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 主体背景采用深蓝色和黑色的渐变，增加科技感 */
body {
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #001f3f 70%, #000000 30%);
    color: #FFFFFF;
    line-height: 1.6;
    padding: 20px;
}

/* 导航栏样式，固定在顶部，包含主要功能入口 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(0, 31, 63, 0.9);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 50px;
}

.navbar .logo {
    font-size: 1.5em;
    font-weight: bold;
    color: #7FDBFF;
}

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

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

.navbar ul li a {
    text-decoration: none;
    color: #FFFFFF;
    font-size: 1em;
    transition: color 0.3s ease;
}

.navbar ul li a:hover {
    color: #2ECC40;
}

/* 主要内容区域，留出导航栏高度 */
.main-content {
    margin-top: 80px;
    display: grid;
    grid-template-columns: 1fr 3fr 1fr;
    gap: 20px;
}

/* 文章内容区域 */
article {
    background-color: rgba(0, 31, 63, 0.8);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}

/* 文章标题样式 */
article h2, article h3 {
    color: #7FDBFF;
    margin-bottom: 15px;
}

article h2 {
    font-size: 2em;
}

article h3 {
    font-size: 1.5em;
}

/* 段落和代码块样式 */
article p {
    font-size: 1em;
    margin-bottom: 15px;
}

article pre {
    background-color: #001f3f;
    padding: 10px;
    border-radius: 5px;
    overflow-x: auto;
}

article code {
    color: #7FDBFF;
    font-family: 'Courier New', Courier, monospace;
}

/* 图片样式，圆角、阴影和悬浮效果 */
img.decorative {
    width: 100%;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

img.decorative:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 12px rgba(0,0,0,0.5);
}

/* 提示信息的样式，突出显示 */
.highlight {
    background-color: rgba(46, 204, 113, 0.2);
    padding: 10px;
    border-left: 5px solid #2ECC40;
    margin-bottom: 20px;
}

/* 章节导航样式，固定在左侧 */
.sidebar {
    position: fixed;
    top: 80px;
    left: 20px;
    width: 200px;
}

.sidebar ul {
    list-style: none;
}

.sidebar ul li {
    margin-bottom: 10px;
}

.sidebar ul li a {
    text-decoration: none;
    color: #FFFFFF;
    font-size: 0.9em;
    transition: color 0.3s ease;
}

.sidebar ul li a:hover {
    color: #7FDBFF;
}

/* 响应式设计，适配不同屏幕宽度 */
@media (max-width: 1200px) {
    .main-content {
        grid-template-columns: 1fr 2fr;
    }

    .sidebar {
        display: none;
    }
}

@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        align-items: flex-start;
        padding: 10px 20px;
    }

    .navbar ul {
        flex-direction: column;
        width: 100%;
    }

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

    .main-content {
        grid-template-columns: 1fr;
    }
}

/* 动画效果，渐显加载 */
.fade-in {
    opacity: 0;
    animation: fadeIn 2s forwards;
}

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

/* 按钮样式，渐变色和过渡效果 */
.button-primary {
    background: linear-gradient(90deg, #001f3f, #0074D9);
    border: none;
    padding: 10px 20px;
    color: #FFFFFF;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.button-primary:hover {
    background: linear-gradient(90deg, #0074D9, #2ECC40);
}

/* AI助手悬浮框样式 */
.ai-assistant {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background-color: #0074D9;
    border-radius: 50%;
    width: 60px;
    height: 60px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: transform 0.3s ease, background-color 0.3s ease;
}

.ai-assistant:hover {
    transform: scale(1.1);
    background-color: #2ECC40;
}

/* 代码示例块的样式，与文章内容区分 */
.code-sample {
    background-color: #001f3f;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 20px 0;
}

.code-sample code {
    color: #7FDBFF;
    font-family: 'Courier New', Courier, monospace;
}

/* 折叠区域样式 */
.collapsible {
    background-color: rgba(0, 31, 63, 0.8);
    color: #FFFFFF;
    cursor: pointer;
    padding: 10px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 1em;
    margin-bottom: 10px;
}

.active, .collapsible:hover {
    background-color: #0074D9;
}

.content {
    padding: 0 18px;
    display: none;
    overflow: hidden;
    background-color: rgba(0, 31, 63, 0.6);
    border-radius: 5px;
}