/* 奈云 (naiyun.baby) - 纯 CSS 极致响应式样式表 (浅色科技风格) */

:root {
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --bg-subtle: #f1f5f9;
  --bg-hero: linear-gradient(180deg, #edf4ff 0%, #f8fafc 100%);
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --primary-border: #bfdbfe;
  --accent: #0284c7;
  --accent-green: #10b981;
  --gradient-brand: linear-gradient(135deg, #2563eb 0%, #0284c7 100%);
  --gradient-badge: linear-gradient(135deg, #dbeafe 0%, #e0f2fe 100%);
  --gradient-card-highlight: linear-gradient(180deg, #ffffff 0%, #eff6ff 100%);
  
  --border-color: #e2e8f0;
  --border-hover: #cbd5e1;
  
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.07);
  --shadow-lg: 0 12px 24px rgba(37, 99, 235, 0.08);
  --shadow-xl: 0 20px 32px rgba(37, 99, 235, 0.12);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --container-width: 1200px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

/* 全局重置与基础设置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: all 0.2s ease;
}

a:hover {
  color: var(--primary-hover);
}

img, svg {
  max-width: 100%;
  height: auto;
  vertical-align: middle;
}

/* 布局容器 */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section-padding {
  padding: 80px 0;
}

.text-center {
  text-center: center;
  text-align: center;
}

.section-title-wrap {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 50px auto;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  background: var(--gradient-badge);
  color: var(--primary);
  font-size: 0.875rem;
  font-weight: 600;
  border: 1px solid var(--primary-border);
  margin-bottom: 16px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.025em;
  margin-bottom: 16px;
  line-height: 1.25;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
}

/* 按钮样式 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  border: none;
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-brand);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
  color: #ffffff;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.45);
}

.btn-secondary {
  background-color: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--bg-subtle);
  border-color: var(--border-hover);
  color: var(--primary);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.125rem;
  border-radius: var(--radius-md);
}

.btn-full {
  width: 100%;
}

/* 导航栏 */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.375rem;
  font-weight: 800;
  color: var(--text-primary);
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--gradient-brand);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
}

.nav-links a:hover {
  color: var(--primary);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* 主视觉区 Hero */
.hero-section {
  background: var(--bg-hero);
  padding: 80px 0 100px 0;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border-color);
}

.hero-content {
  text-align: center;
  max-width: 860px;
  margin: 0 auto;
}

.hero-title {
  font-size: 3.25rem;
  font-weight: 900;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: 24px;
  letter-spacing: -0.03em;
}

.highlight-text {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 36px;
}

.hero-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 48px;
}

.hero-features-strip {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 28px;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
}

.feature-strip-item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.feature-strip-item svg {
  color: var(--accent-green);
}

/* 核心优势卡片 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-sm);
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: var(--primary-border);
  box-shadow: var(--shadow-lg);
}

.feature-icon-box {
  width: 54px;
  height: 54px;
  border-radius: var(--radius-md);
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text-primary);
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* 流媒体与 AI 支持 */
.ecosystem-section {
  background-color: var(--bg-subtle);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.eco-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 20px;
}

.eco-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px 16px;
  text-align: center;
  transition: all 0.25s ease;
  box-shadow: var(--shadow-sm);
}

.eco-card:hover {
  border-color: var(--primary-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.eco-icon {
  width: 44px;
  height: 44px;
  margin: 0 auto 12px auto;
  display: flex;
  align-items: center;
  justify-content: center;
}

.eco-card h4 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.eco-card p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* 价格对比表 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-sm);
}

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

.pricing-card.popular {
  border: 2px solid var(--primary);
  background: var(--gradient-card-highlight);
  box-shadow: var(--shadow-xl);
}

.popular-badge {
  position: absolute;
  top: -14px;
  right: 28px;
  background: var(--gradient-brand);
  color: white;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pricing-header {
  margin-bottom: 24px;
}

.plan-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  min-height: 40px;
}

.plan-price {
  margin: 20px 0;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.currency {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.amount {
  font-size: 2.75rem;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1;
}

.period {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.plan-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 14px;
}

.plan-features li svg {
  color: var(--accent-green);
  flex-shrink: 0;
}

/* 用户评价 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
}

.stars {
  color: #f59e0b;
  display: flex;
  gap: 4px;
  margin-bottom: 16px;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  font-style: italic;
}

.user-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-full);
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--primary-border);
}

.user-details h5 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.user-details p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* FAQ 常见问题 */
.faq-wrap {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: all 0.2s ease;
}

.faq-item[open] {
  border-color: var(--primary-border);
  box-shadow: var(--shadow-sm);
}

.faq-summary {
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.faq-summary::-webkit-details-marker {
  display: none;
}

.faq-summary::after {
  content: "+";
  font-size: 1.25rem;
  font-weight: 400;
  color: var(--text-muted);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-summary::after {
  content: "−";
  color: var(--primary);
}

.faq-content {
  padding: 0 24px 20px 24px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  border-top: 1px solid var(--bg-subtle);
  padding-top: 16px;
}

/* 页脚 - 约束：只保留4个独立页面跳转标题 */
.footer {
  background: #ffffff;
  border-top: 1px solid var(--border-color);
  padding: 50px 0 30px 0;
  margin-top: auto;
}

.footer-top {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 28px;
  margin-bottom: 36px;
  text-align: center;
}

.footer-nav-titles {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 36px;
  list-style: none;
}

.footer-nav-titles li a {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}

.footer-nav-titles li a:hover {
  color: var(--primary);
  background-color: var(--primary-light);
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* 通用子页面样式 */
.page-header {
  background: var(--bg-hero);
  padding: 60px 0 40px 0;
  border-bottom: 1px solid var(--border-color);
  text-align: center;
}

.page-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.page-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
}

.content-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 60px;
}

.content-box h2 {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 32px 0 16px 0;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-light);
}

.content-box h2:first-child {
  margin-top: 0;
}

.content-box p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  font-size: 0.975rem;
  line-height: 1.7;
}

.content-box ul {
  margin: 0 0 20px 24px;
  color: var(--text-secondary);
}

.content-box ul li {
  margin-bottom: 8px;
  font-size: 0.95rem;
}

/* 网站地图样式 */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.sitemap-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
}

.sitemap-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.sitemap-list {
  list-style: none;
}

.sitemap-list li {
  margin-bottom: 10px;
}

.sitemap-list a {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.sitemap-list a:hover {
  color: var(--primary);
  padding-left: 4px;
}

/* 响应式适配 - 手机端单栏优化 */
@media (max-width: 768px) {
  .section-padding {
    padding: 50px 0;
  }
  
  .navbar {
    height: 64px;
  }
  
  .nav-links {
    display: none; /* 移动端精简导航 */
  }
  
  .hero-title {
    font-size: 2.125rem;
  }
  
  .hero-subtitle {
    font-size: 1rem;
  }
  
  .hero-cta {
    flex-direction: column;
    width: 100%;
  }
  
  .btn {
    width: 100%;
    padding: 14px 20px;
  }
  
  .pricing-grid,
  .features-grid,
  .eco-grid,
  .reviews-grid,
  .sitemap-grid {
    grid-template-columns: 1fr; /* 手机端单栏展示 */
  }
  
  .footer-nav-titles {
    flex-direction: column;
    gap: 16px;
  }
  
  .content-box {
    padding: 24px 18px;
  }
  
  .section-title {
    font-size: 1.75rem;
  }
}