/* ==========================================================================
   九云机场 (9-Cloud) 官方核心样式库 - 原生纯 CSS 极简秒开架构
   ========================================================================== */

:root {
  /* 亮色海洋蓝 (Light Ocean Blue) - 饱满深湛海天蓝版 */
  --bg-primary: #cde6fc;
  --bg-secondary: #b8dcfa;
  --bg-card: #ffffff;
  --bg-card-hover: #f3f9ff;
  --border-color: #9ccdf5;
  --border-focus: #0284c7;
  
  --text-main: #071f3d;
  --text-muted: #1a3c61;
  --text-dim: #3e668e;
  
  --accent-cyan: #0284c7;
  --accent-blue: #0284c7;
  --accent-indigo: #0369a1;
  --accent-green: #059669;
  --accent-gradient: linear-gradient(135deg, #0284c7 0%, #0369a1 50%, #0ea5e9 100%);
  --cta-gradient: linear-gradient(135deg, #0284c7 0%, #0369a1 100%);
  --cta-hover: linear-gradient(135deg, #0369a1 0%, #075985 100%);
  
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --container-width: 1200px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --transition: all 0.25s ease-in-out;
}

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

html {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* 键盘无障碍跳过导航 */
.skip-link {
  position: absolute;
  top: -60px;
  left: 20px;
  background: var(--accent-blue);
  color: #ffffff;
  padding: 12px 20px;
  z-index: 9999;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
  transition: top 0.2s ease;
}
.skip-link:focus {
  top: 20px;
  outline: 3px solid #ffffff;
}

/* 锚点防遮挡 */
section, h1, h2, h3, [id] {
  scroll-margin-top: 90px;
}

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

/* 顶部导航栏 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(184, 220, 250, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 74px;
}

.logo-area {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-main);
}

.logo-img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  display: block;
  box-shadow: 0 4px 14px rgba(2, 132, 199, 0.25);
  transition: var(--transition);
}

.logo-area:hover .logo-img {
  transform: translateY(-2px) scale(1.04);
  box-shadow: 0 6px 18px rgba(2, 132, 199, 0.35);
}

.logo-icon {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 800;
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(6, 182, 212, 0.3);
}

.logo-text {
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: var(--transition);
  padding: 8px 4px;
  position: relative;
}

.nav-link:hover, .nav-link:focus {
  color: var(--text-main);
  outline: none;
}

.nav-link.active {
  color: var(--accent-cyan);
  font-weight: 600;
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  min-width: 108px;
  padding: 0 20px;
  background: var(--cta-gradient);
  color: #ffffff !important;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.nav-cta:hover, .nav-cta:focus {
  background: var(--cta-hover);
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.5);
  outline: 2px solid var(--border-focus);
}

/* 按钮通用规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  text-align: center;
}

.btn-primary {
  background: var(--cta-gradient);
  color: #ffffff;
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.4);
}
.btn-primary:hover, .btn-primary:focus {
  background: var(--cta-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.55);
  outline: 2px solid var(--border-focus);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-main);
  border: 1px solid var(--border-color);
}
.btn-secondary:hover, .btn-secondary:focus {
  background: var(--bg-card-hover);
  border-color: var(--accent-cyan);
  outline: 2px solid var(--accent-cyan);
}

/* 主视觉区 (Hero) */
.hero-section {
  padding: 72px 0 60px;
  position: relative;
  text-align: center;
  background: radial-gradient(circle at 50% 20%, rgba(2, 132, 199, 0.22) 0%, rgba(205, 230, 252, 0) 70%);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(2, 132, 199, 0.12);
  border: 1px solid rgba(2, 132, 199, 0.35);
  border-radius: 999px;
  color: var(--accent-cyan);
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(2rem, 4vw + 1rem, 3.25rem);
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

.hero-title-gradient {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 16px;
}

.hero-desc {
  max-width: 780px;
  margin: 0 auto 36px;
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.75;
}

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

.hero-trust {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
  font-size: 0.9rem;
  color: var(--text-dim);
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
}
.trust-item strong {
  color: var(--accent-cyan);
}

/* 通用区块排版 */
.section {
  padding: 72px 0;
  border-top: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 48px;
}

.section-tag {
  display: inline-block;
  color: var(--accent-cyan);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(1.6rem, 2.5vw + 0.5rem, 2.25rem);
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--text-main);
}

.section-desc {
  font-size: 1rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* 核心优势卡片 (3 Cards) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  box-shadow: 0 4px 16px rgba(2, 132, 199, 0.06);
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-cyan);
  background: var(--bg-card-hover);
  box-shadow: 0 12px 30px rgba(2, 132, 199, 0.15);
}

.feature-icon-wrapper {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-sm);
  background: rgba(2, 132, 199, 0.08);
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  font-size: 26px;
}

.feature-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main);
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
  flex-grow: 1;
}

.feature-list {
  list-style: none;
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--border-color);
}

.feature-list li {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.feature-list li::before {
  content: "✓";
  color: var(--accent-green);
  font-weight: bold;
}

/* 流媒体与 AI 支持图卡 */
.media-ai-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.support-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 36px;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
  box-shadow: 0 4px 16px rgba(2, 132, 199, 0.06);
}
.support-card:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 10px 28px rgba(2, 132, 199, 0.14);
}

.support-card h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main);
}

.support-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.badge-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.badge-tag {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* 套餐价格对比表 */
.pricing-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background: var(--bg-card);
  box-shadow: 0 10px 30px rgba(2, 132, 199, 0.08);
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  min-width: 720px;
}

.pricing-table caption {
  padding: 16px 24px;
  text-align: left;
  font-size: 0.95rem;
  color: var(--text-dim);
  border-bottom: 1px solid var(--border-color);
  background: var(--bg-secondary);
  font-weight: 500;
}

.pricing-table th, .pricing-table td {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border-color);
  vertical-align: middle;
}

.pricing-table th {
  background: var(--bg-secondary);
  color: var(--text-main);
  font-size: 0.92rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.pricing-table tbody tr:hover {
  background: rgba(2, 132, 199, 0.03);
}

.pricing-table tbody tr.popular {
  background: rgba(2, 132, 199, 0.06);
  border-left: 3px solid var(--accent-cyan);
}

.plan-name {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  display: block;
}

.plan-tag {
  display: inline-block;
  font-size: 0.75rem;
  padding: 2px 8px;
  background: var(--accent-cyan);
  color: #ffffff;
  font-weight: 800;
  border-radius: 4px;
  margin-top: 4px;
}

.price-box {
  display: flex;
  align-items: baseline;
  gap: 2px;
}

.price-currency {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.price-number {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text-main);
}

.price-period {
  font-size: 0.85rem;
  color: var(--text-dim);
}

.table-cta {
  min-height: 42px;
  padding: 0 18px;
  font-size: 0.9rem;
}

/* 用户评价区 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  box-shadow: 0 4px 16px rgba(2, 132, 199, 0.05);
}

.review-stars {
  color: #f59e0b;
  font-size: 1.1rem;
  margin-bottom: 12px;
  letter-spacing: 2px;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--accent-cyan);
}

.author-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

.author-info p {
  font-size: 0.82rem;
  color: var(--text-dim);
}

/* 常见问题 (FAQ) - 原生 details 默认展开 */
.faq-list {
  max-width: 860px;
  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: var(--transition);
  box-shadow: 0 2px 10px rgba(2, 132, 199, 0.05);
}

.faq-item[open] {
  border-color: var(--accent-cyan);
}

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

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

.faq-summary::after {
  content: "▾";
  font-size: 1.25rem;
  color: var(--accent-cyan);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-summary::after {
  transform: rotate(180deg);
}

.faq-summary:focus-visible {
  outline: 2px solid var(--border-focus);
}

.faq-answer {
  padding: 0 24px 24px;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.75;
  border-top: 1px solid var(--border-color);
  padding-top: 16px;
}

.faq-answer a {
  color: var(--accent-cyan);
  text-decoration: underline;
}

/* 知识科普专区与文章网格 */
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
  text-decoration: none;
  color: inherit;
  box-shadow: 0 4px 16px rgba(2, 132, 199, 0.06);
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-cyan);
  box-shadow: 0 12px 30px rgba(2, 132, 199, 0.14);
}

.article-card-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.82rem;
  color: var(--text-dim);
  margin-bottom: 12px;
}

.article-tag {
  background: rgba(2, 132, 199, 0.1);
  color: var(--accent-cyan);
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
}

.article-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main);
  line-height: 1.45;
}

.article-card p {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.65;
  flex-grow: 1;
  margin-bottom: 20px;
}

.article-card-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent-cyan);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* 文章详情页排版 */
.article-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 48px 24px 80px;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text-dim);
  margin-bottom: 24px;
}

.breadcrumb a {
  color: var(--text-muted);
  text-decoration: none;
}
.breadcrumb a:hover {
  color: var(--accent-cyan);
}

.article-header {
  margin-bottom: 36px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 28px;
}

.article-header h1 {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 800;
  line-height: 1.35;
  margin-bottom: 16px;
  color: var(--text-main);
}

.article-meta-bar {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.9rem;
  color: var(--text-dim);
  flex-wrap: wrap;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.85;
  color: #1e293b;
}

.article-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 40px 0 16px;
  color: var(--text-main);
  border-left: 4px solid var(--accent-cyan);
  padding-left: 12px;
}

.article-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 28px 0 12px;
  color: var(--text-main);
}

.article-content p {
  margin-bottom: 20px;
}

.article-content ul, .article-content ol {
  margin: 0 0 24px 24px;
}

.article-content li {
  margin-bottom: 10px;
}

.article-content a {
  color: var(--accent-cyan);
  text-decoration: underline;
  font-weight: 600;
}

.article-content blockquote {
  border-left: 4px solid var(--accent-cyan);
  background: var(--bg-secondary);
  padding: 16px 20px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 24px 0;
  font-style: italic;
  color: var(--text-muted);
}

.article-cta-box {
  background: linear-gradient(135deg, rgba(2, 132, 199, 0.06) 0%, rgba(14, 165, 233, 0.1) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 32px;
  text-align: center;
  margin: 48px 0;
  box-shadow: 0 4px 16px rgba(2, 132, 199, 0.05);
}

.article-cta-box h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main);
}

.article-cta-box p {
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto 24px;
}

/* 页脚 (严格只保留四个链接打开新页) */
.site-footer {
  margin-top: auto;
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 48px 0 36px;
}

.footer-nav-list {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 36px;
  list-style: none;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

.footer-nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 1rem;
  font-weight: 600;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.footer-nav-link:hover, .footer-nav-link:focus {
  color: var(--accent-cyan);
  outline: 2px solid var(--border-focus);
}

.footer-bottom {
  text-align: center;
  font-size: 0.88rem;
  color: var(--text-dim);
  border-top: 1px solid var(--border-color);
  padding-top: 24px;
}

/* 响应式媒体查询 (@media) */
@media (max-width: 1024px) {
  .features-grid, .reviews-grid, .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: auto;
    min-height: 64px;
    padding: 10px 0;
    flex-wrap: wrap;
    gap: 8px 12px;
  }
  .main-nav {
    order: 3;
    width: 100%;
    overflow-x: auto;
    white-space: nowrap;
    padding: 6px 0;
    gap: 16px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  .main-nav::-webkit-scrollbar {
    display: none;
  }
  .nav-link {
    font-size: 0.9rem;
    padding: 6px 4px;
    flex-shrink: 0;
  }
  .nav-cta {
    min-height: 40px;
    padding: 0 16px;
    font-size: 0.88rem;
  }
  
  .hero-section {
    padding: 48px 0 40px;
  }
  
  .features-grid, .media-ai-grid, .reviews-grid, .article-grid {
    grid-template-columns: 1fr;
  }
  
  .hero-actions {
    flex-direction: column;
    width: 100%;
  }
  .hero-actions .btn {
    width: 100%;
  }
  
  .footer-nav-list {
    gap: 18px;
  }
  
  .pricing-table th, .pricing-table td {
    padding: 16px 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}