:root {
  --primary-color: #00b4db;
  --secondary-color: #0083b0;
  --text-dark: #333333;
  --text-light: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.95);
  --bg-card-hover: rgba(255, 255, 255, 1);
  --border-radius: 12px;
  --transition: all 0.3s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "KaiTi", "楷体", "STKaiti", "华文楷体", serif;
  background: linear-gradient(to right, rgb(0, 180, 219), rgb(0, 131, 176));
  color: var(--text-dark);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

ul {
  list-style: none;
}

/* 导航栏 */
header {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 15px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 24px;
  font-weight: bold;
  color: var(--text-dark);
  letter-spacing: 1px;
}

.nav-links {
  display: flex;
  gap: 20px;
}

.nav-links a {
  color: var(--text-dark);
  font-size: 18px;
}

.nav-links a:hover {
  color: #ffde00;
}

.btn-primary {
  background: #ffaa00;
  color: #fff;
  padding: 10px 24px;
  border-radius: 30px;
  font-size: 18px;
  font-weight: bold;
  display: inline-block;
  border: none;
  cursor: pointer;
}

.btn-primary:hover {
  background: #ff8c00;
  transform: translateY(-2px);
}

/* 主容器 */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 20px;
}

/* Hero Section */
.hero {
  text-align: center;
  color: var(--text-light);
  padding: 80px 20px;
}

.hero h1 {
  font-size: 48px;
  margin-bottom: 20px;
}

.hero p {
  font-size: 20px;
  margin-bottom: 40px;
  opacity: 0.9;
}

/* 模块通用样式 */
.section-title {
  text-align: center;
  color: var(--text-light);
  font-size: 32px;
  margin-bottom: 40px;
  padding-top: 40px;
}

/* 卖点卡片 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
  margin-bottom: 60px;
}

.feature-card {
  background: var(--bg-card);
  padding: 30px 20px;
  border-radius: var(--border-radius);
  text-align: center;
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-5px);
  background: var(--bg-card-hover);
}

.feature-icon {
  font-size: 40px;
  color: var(--primary-color);
  margin-bottom: 15px;
}

.feature-card h3 {
  font-size: 22px;
  margin-bottom: 10px;
}

.feature-card p {
  font-size: 16px;
  color: #666;
}

/* 套餐价格 */
.pricing-grid {
  display: flex;
  flex-direction: column;
  gap: 15px;
  background: var(--bg-card);
  padding: 20px;
  border-radius: var(--border-radius);
}

.pricing-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 30px;
  background: #fff;
  border: 1px solid #eee;
  border-radius: 8px;
  transition: var(--transition);
}

.pricing-card:hover {
  border-color: var(--primary-color);
}

.pricing-card.popular {
  background: var(--secondary-color);
  color: #fff;
  border-color: var(--secondary-color);
}

.pricing-card.popular .plan-desc,
.pricing-card.popular .plan-price {
  color: rgba(255, 255, 255, 0.9);
}

.plan-info {
  flex: 1;
}

.plan-num {
  font-size: 12px;
  color: #999;
}

.popular .plan-num {
  color: rgba(255, 255, 255, 0.6);
}

.plan-name {
  font-size: 24px;
  font-weight: bold;
  margin: 5px 0;
}

.plan-desc {
  font-size: 14px;
  color: #666;
}

.plan-details {
  flex: 2;
  display: flex;
  justify-content: space-around;
  text-align: center;
}

.detail-item span {
  display: block;
  font-size: 12px;
  color: #999;
}

.popular .detail-item span {
  color: rgba(255, 255, 255, 0.6);
}

.detail-item strong {
  font-size: 18px;
}

.plan-price {
  flex: 1;
  text-align: right;
  font-size: 28px;
  font-weight: bold;
}

.plan-price span {
  font-size: 14px;
  font-weight: normal;
}

.plan-action {
  flex: 1;
  text-align: right;
}

.btn-buy {
  background: #222;
  color: #fff;
  padding: 10px 20px;
  border-radius: 4px;
  font-size: 16px;
  border: none;
  cursor: pointer;
}

.popular .btn-buy {
  background: #fff;
  color: var(--text-dark);
}

.btn-buy:hover {
  background: #444;
}

.popular .btn-buy:hover {
  background: #f0f0f0;
}

/* 文章、教程、排查 */
.content-section {
  background: var(--bg-card);
  padding: 40px;
  border-radius: var(--border-radius);
  margin-bottom: 40px;
}

.content-section h2 {
  font-size: 28px;
  margin-bottom: 20px;
  border-bottom: 2px solid #eee;
  padding-bottom: 10px;
}

.article-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 15px;
}

.article-list li a {
  display: block;
  padding: 15px;
  background: #f9f9f9;
  border-radius: 8px;
  color: var(--secondary-color);
  font-size: 18px;
}

.article-list li a:hover {
  background: #eee;
  color: var(--primary-color);
}

/* FAQ 和 用户评价 */
.faq-item {
  margin-bottom: 20px;
}
.faq-item h4 {
  font-size: 20px;
  margin-bottom: 5px;
  color: var(--primary-color);
}

.review-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.review-item {
  background: #f9f9f9;
  padding: 20px;
  border-radius: 8px;
  border-left: 4px solid var(--primary-color);
}
.review-user {
  font-weight: bold;
  margin-bottom: 5px;
}

/* 底部 */
footer {
  text-align: center;
  color: rgba(255,255,255,0.7);
  padding: 40px 20px;
  border-top: 1px solid rgba(255,255,255,0.1);
  margin-top: 40px;
}

/* 响应式 */
@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .hero h1 {
    font-size: 36px;
  }
  .pricing-card {
    flex-direction: column;
    text-align: center;
    gap: 15px;
  }
  .plan-details {
    flex-direction: column;
    gap: 10px;
  }
  .plan-action {
    text-align: center;
  }
}