/* 全局样式设置，确保整个页面的字体、背景颜色及基本布局 */
/* 采用深蓝色作为主背景色，搭配灰色和白色，点缀以电光蓝和绿松石 */
body {
  margin: 0;
  padding: 0;
  background: linear-gradient(135deg, #1A237E 70%, #455A64 25%, #00E676 5%);
  font-family: 'Roboto', sans-serif;
  color: #FFFFFF;
  line-height: 1.6;
}

/* 设置标题样式，确保层次分明 */
h2, h3, h4 {
  margin: 20px 0;
  color: #FFFFFF;
}

h2 {
  font-size: 24px;
}

h3 {
  font-size: 20px;
}

h4 {
  font-size: 18px;
}

/* 导航栏样式，采用不对称斜向设计 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 220px;
  height: 100%;
  background-color: #455A64;
  transform: skewY(-3deg);
  display: flex;
  flex-direction: column;
  padding: 40px 20px;
  box-shadow: 2px 0 5px rgba(0,0,0,0.5);
}

.navbar a {
  color: #FFFFFF;
  text-decoration: none;
  margin: 15px 0;
  transition: color 0.3s, transform 0.3s;
}

.navbar a:hover {
  color: #29B6F6;
  transform: scale(1.05);
}

/* 主内容区域，采用网格布局实现响应式设计 */
.main-content {
  margin-left: 240px;
  padding: 60px 40px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 30px;
}

/* 文章区块样式，独立的视觉区块 */
.article-section {
  background-color: rgba(255, 255, 255, 0.1);
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.3);
}

/* 按钮样式，采用渐变效果 */
.button {
  background: linear-gradient(45deg, #29B6F6, #00E676);
  border: none;
  padding: 12px 25px;
  color: #FFFFFF;
  cursor: pointer;
  border-radius: 25px;
  transition: background 0.3s, transform 0.3s;
  font-size: 16px;
}

.button:hover {
  background: linear-gradient(45deg, #00E676, #29B6F6);
  transform: translateY(-3px);
}

/* 图片样式，添加圆角、阴影和悬浮效果 */
.decorative-image {
  width: 100%;
  border-radius: 15px;
  box-shadow: 0 4px 15px rgba(0,0,0,0.3);
  transition: transform 0.3s, box-shadow 0.3s;
}

.decorative-image:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 20px rgba(0,0,0,0.4);
}

/* 代码块样式，与正文内容区分开 */
.code-block {
  background-color: rgba(0,0,0,0.7);
  padding: 15px;
  border-radius: 10px;
  overflow-x: auto;
  font-family: 'Courier New', Courier, monospace;
  color: #00E676;
  margin: 20px 0;
}

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

/* 段落和链接的样式 */
p {
  font-size: 16px;
  color: #FFFFFF;
}

p a {
  color: #29B6F6;
  text-decoration: none;
  transition: color 0.3s;
}

p a:hover {
  color: #00E676;
}

/* 卡片式布局样式，用于展示示例数据 */
.card-container {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

.card {
  background-color: rgba(255, 255, 255, 0.2);
  border-radius: 10px;
  padding: 20px;
  flex: 1 1 calc(33% - 40px);
  box-shadow: 0 4px 10px rgba(0,0,0,0.2);
  transition: transform 0.3s, box-shadow 0.3s;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.3);
}

/* 章节导航系统样式，固定在页面顶部 */
.chapter-nav {
  position: fixed;
  top: 0;
  right: 0;
  width: 200px;
  background-color: #455A64;
  padding: 20px;
  box-shadow: -2px 0 5px rgba(0,0,0,0.5);
}

.chapter-nav a {
  display: block;
  color: #FFFFFF;
  text-decoration: none;
  margin: 10px 0;
  transition: color 0.3s;
}

.chapter-nav a:hover {
  color: #29B6F6;
}

/* 响应式设计，适配不同屏幕尺寸 */
/* 对于小于768px的设备，调整导航栏和内容区域 */
@media (max-width: 768px) {
  .navbar {
    width: 100%;
    height: auto;
    transform: none;
    flex-direction: row;
    justify-content: space-around;
  }
  
  .main-content {
    margin: 0;
    padding: 20px;
    grid-template-columns: 1fr;
  }
  
  .chapter-nav {
    display: none;
  }
}

/* 特殊样式，用于提示信息 */
.prompt-message {
  text-align: center;
  font-size: 18px;
  margin: 40px 0;
  color: #FFEB3B;
  font-weight: bold;
  animation: fadeIn 2s ease-in-out;
}

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