.app-container {
  display: flex;
  height: 100vh;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* 左侧菜单样式 */
.sidebar {
  max-width: 250px;
  min-width: 150px;
  width: 18%;
  background: linear-gradient(180deg, #2c3e50 0%, #34495e 100%);
  color: white;
  display: flex;
  flex-direction: column;
  box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
}

.nav-menu {
  flex: 1;
  padding: 20px 0;
}

.nav-item {
  display: flex;
  align-items: center;
  padding: 15px 20px;
  cursor: pointer;
  transition: all 0.3s ease;
  border-left: 3px solid transparent;
}

.nav-item:hover {
  background-color: #34495e;
  border-left-color: #3498db;
}

.nav-item.active {
  background-color: #3498db;
  border-left-color: #2980b9;
}

.nav-item .icon {
  font-size: 18px;
  margin-right: 12px;
  width: 20px;
  text-align: center;
}

.nav-item span {
  font-size: 16px;
  font-weight: 500;
}

/* 右侧内容区域样式 */
.main-content {
  flex: 1;
  padding: 30px;
  background-color: #f8f9fa;
  overflow-y: auto;
}

.content-section h1 {
  color: #2c3e50;
  margin-bottom: 30px;
  font-size: 32px;
  font-weight: 600;
}

.intro-card, .example-card {
  background: white;
  border-radius: 12px;
  padding: 30px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  margin-bottom: 20px;
}

.intro-card h3, .example-card h3 {
  color: #2c3e50;
  margin-bottom: 15px;
  font-size: 24px;
}

.intro-card h4 {
  color: #34495e;
  margin: 25px 0 15px 0;
  font-size: 18px;
}

.intro-card p {
  color: #7f8c8d;
  line-height: 1.6;
  font-size: 16px;
}

.intro-card ul {
  color: #7f8c8d;
  line-height: 1.8;
}

.intro-card li {
  margin-bottom: 8px;
}

.tech-stack {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 15px;
}

.tech-tag {
  background: linear-gradient(135deg, #3498db, #2980b9);
  color: white;
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 500;
}

.code-example {
  margin-bottom: 25px;
}

.code-example h4 {
  color: #2c3e50;
  margin-bottom: 10px;
  font-size: 16px;
}

.code-example pre {
  background: #2c3e50;
  color: #ecf0f1;
  padding: 20px;
  border-radius: 8px;
  overflow-x: auto;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.5;
}

.action-buttons {
  display: flex;
  gap: 15px;
  margin-top: 25px;
  flex-wrap: wrap;
}

.demo-btn {
  background: linear-gradient(135deg, #3498db, #2980b9);
  color: white;
  border: none;
  padding: 12px 20px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 500;
  transition: all 0.3s ease;
}

.demo-btn:hover {
  background: linear-gradient(135deg, #2980b9, #1f5f8b);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(52, 152, 219, 0.3);
}

.demo-btn:active {
  transform: translateY(0);
}

/* 滚动条样式 */
.main-content::-webkit-scrollbar {
  width: 8px;
}

.main-content::-webkit-scrollbar-track {
  background: #f1f1f1;
  border-radius: 4px;
}

.main-content::-webkit-scrollbar-thumb {
  background: #bdc3c7;
  border-radius: 4px;
}

.main-content::-webkit-scrollbar-thumb:hover {
  background: #95a5a6;
}