/* 根元素设置，包含全局字体和背景色 */
:root {
    --main-color: #1E272E; /* 主色调：深蓝色 */
    --secondary-color: #AAB8C2; /* 辅色调：灰色 */
    --accent-color: #FFA500; /* 点缀色：亮橙色 */
    --background-gradient: linear-gradient(135deg, #1E272E, #AAB8C2); /* 背景线性渐变 */
    --font-family: 'Roboto', sans-serif; /* 全局字体 */
}

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

/* 设置全局字体和背景色 */
body {
    font-family: var(--font-family);
    background: var(--background-gradient);
    color: #FFFFFF;
    line-height: 1.6;
    overflow-x: hidden; /* 避免水平滚动条 */
}

/* 导航栏样式 */
nav {
    background: rgba(30, 39, 46, 0.9); /* 半透明背景 */
    padding: 20px 40px; /* 内边距 */
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3); /* 阴影效果 */
}

nav .logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--accent-color);
}

nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
}

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

nav ul li a:hover {
    color: var(--accent-color);
}

/* 主容器，避免内容被导航栏遮挡 */
.main-container {
    padding: 100px 20px 20px 20px; /* 上边距留出导航栏空间 */
    max-width: 1200px;
    margin: 0 auto;
}

/* 提示信息样式 */
.reference-note {
    background: rgba(255, 255, 255, 0.1);
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 40px;
    text-align: center;
    font-size: 1.2rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

/* 文章样式 */
article {
    background: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

article h2, article h3 {
    color: var(--accent-color);
    margin-bottom: 20px;
}

article p {
    margin-bottom: 20px;
    font-size: 16px;
}

article pre {
    background: rgba(170, 184, 194, 0.2);
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin-bottom: 20px;
    position: relative;
}

article pre code {
    font-family: 'Courier New', Courier, monospace;
    color: #FFFFFF;
    font-size: 14px;
}

/* 代码块标题 */
pre code::before {
    content: "代码示例";
    display: block;
    font-size: 14px;
    font-weight: bold;
    margin-bottom: 10px;
}

/* 图片样式 */
img.decoration {
    width: 320px;
    height: 320px;
    object-fit: cover;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

img.decoration:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.5);
}

/* 图文并茂的模块样式 */
.section {
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
    margin-bottom: 60px;
}

.section .text-content {
    flex: 1 1 500px; /* 不低于500px宽度 */
}

.section .image-content {
    flex: 1 1 320px;
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

.section .image-content img {
    flex: 1 1 calc(50% - 20px);
}

/* 微交互与动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section .text-content, .reference-note {
    animation: fadeInUp 1s ease-out forwards;
    opacity: 0;
    transform: translateY(20px);
}

.section .text-content.visible, .reference-note.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 按钮样式 */
.button {
    background-color: var(--accent-color);
    color: #FFFFFF;
    padding: 15px 30px;
    border: none;
    border-radius: 5px;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.button:hover {
    background-color: #FF8C00;
}

/* 折叠区域样式 */
.collapsible {
    background-color: rgba(255, 255, 255, 0.1);
    color: #FFFFFF;
    cursor: pointer;
    padding: 18px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 16px;
    transition: background-color 0.3s ease;
    border-radius: 5px;
    margin-bottom: 10px;
}

.collapsible:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

.collapsible.active, .collapsible:focus {
    background-color: rgba(255, 255, 255, 0.2);
}

.content {
    padding: 0 18px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    background-color: rgba(255, 255, 255, 0.05);
    border-radius: 5px;
    margin-bottom: 20px;
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .section {
        flex-direction: column;
    }

    nav ul {
        flex-direction: column;
        gap: 10px;
    }
}

@media (max-width: 768px) {
    nav {
        padding: 15px 20px;
    }

    .section .image-content img {
        flex: 1 1 100%;
    }
}

@media (max-width: 480px) {
    .reference-note {
        padding: 15px;
        font-size: 1rem;
    }

    article {
        padding: 20px;
    }

    .button {
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
        display: block;
    }
}