/* 极速cloud机场 - 现代化极简原生样式表 (晴空蓝主题 Clear Sky Blue) */
:root {
  --primary: #0284c7;
  --primary-hover: #0369a1;
  --primary-light: rgba(2, 132, 199, 0.09);
  --accent: #0284c7;
  --accent-light: #38bdf8;
  --bg-main: #edf6fd;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fbff;
  --bg-elevated: #e0f2fe;
  --text-heading: #0c2340;
  --text-main: #1e293b;
  --text-muted: #334155;
  --text-dim: #64748b;
  --border-color: #bae6fd;
  --border-card: #e0f2fe;
  --border-focus: #0284c7;
  --success: #059669;
  --warning: #d97706;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  --shadow-sm: 0 2px 4px rgba(2, 132, 199, 0.05);
  --shadow-md: 0 4px 14px rgba(2, 132, 199, 0.08);
  --shadow-lg: 0 10px 30px rgba(2, 132, 199, 0.12);
  --max-width: 1200px;
  --header-height: 72px;
}

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

html {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-main);
  background-color: var(--bg-main);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

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

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: #dbeafe;
  background-image: linear-gradient(180deg, #7ecaf7 0%, #b8e2fd 260px, #e0f2fe 540px, #f4faff 100%);
  background-attachment: fixed;
  color: var(--text-main);
  word-wrap: break-word;
  overflow-x: hidden;
  position: relative;
}

/* 晴空微风慢拂白云背景系统 (Gentle Breeze & Drifting White Clouds) */
.clouds-sky-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

/* 远景高空薄云与微风气流 (极缓漂移 110s) */
.clouds-drift-layer2 {
  position: absolute;
  top: 0;
  left: 0;
  width: 200%;
  height: 500px;
  background-image: url('images/clouds-layer2.svg');
  background-repeat: repeat-x;
  background-size: 2560px 500px;
  background-position: -300px 0;
  animation: cloudsDriftSlow 110s linear infinite;
  will-change: transform;
  opacity: 0.78;
}

/* 主视景微风白云层 (轻缓飘移 70s) */
.clouds-drift-layer1 {
  position: absolute;
  top: 0;
  left: 0;
  width: 200%;
  height: 600px;
  background-image: url('images/clouds-layer1.svg');
  background-repeat: repeat-x;
  background-size: 2560px 600px;
  background-position: 0 35px;
  animation: cloudsDrift 70s linear infinite;
  will-change: transform;
  opacity: 0.9;
}

@keyframes cloudsDrift {
  0% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(-50%, 0, 0);
  }
}

@keyframes cloudsDriftSlow {
  0% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(-50%, 0, 0);
  }
}

/* 确保所有主体交互图层处于流云上方 */
main,
.site-header,
.site-footer {
  position: relative;
  z-index: 1;
}

/* 键盘可访问性：跳到主要内容 */
.skip-link {
  position: absolute;
  top: -9999px;
  left: 16px;
  background: var(--primary);
  color: #ffffff;
  padding: 12px 20px;
  font-weight: 700;
  border-radius: var(--radius-sm);
  z-index: 10000;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 16px;
  outline: 3px solid #0284c7;
}

/* 焦点高亮 */
a:focus-visible,
button:focus-visible,
summary:focus-visible,
input:focus-visible {
  outline: 3px solid var(--border-focus);
  outline-offset: 3px;
}

/* 锚点防遮挡 */
[id] {
  scroll-margin-top: calc(var(--header-height) + 24px);
}

/* 布局容器 */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* 顶部导航栏 (晴空微透玻璃拟态) */
.site-header {
  position: sticky;
  top: 0;
  width: 100%;
  height: var(--header-height);
  background: rgba(235, 245, 255, 0.94);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  display: flex;
  align-items: center;
  box-shadow: 0 2px 10px rgba(2, 132, 199, 0.05);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.site-logo:hover {
  opacity: 0.92;
  transform: translateY(-1px);
}

.logo-icon {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(2, 132, 199, 0.35);
  display: block;
  flex-shrink: 0;
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-heading);
  letter-spacing: -0.02em;
  display: inline-flex;
  align-items: center;
  line-height: 1;
}

.logo-text-accent {
  background: linear-gradient(135deg, #0284c7, #2563eb);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 900;
  margin-left: 2px;
}

.logo-tag {
  font-size: 0.7rem;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: var(--radius-sm);
  background: #e0f2fe;
  color: #0369a1;
  border: 1px solid #7dd3fc;
  margin-left: 8px;
  line-height: 1.2;
}

.logo-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent-light));
  color: #ffffff;
  border-radius: 10px;
  font-weight: 900;
  font-size: 1.1rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 18px;
  list-style: none;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: color 0.2s ease, background-color 0.2s ease;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background-color: var(--primary-light);
}

.header-cta {
  display: flex;
  align-items: center;
}

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  min-width: 44px;
  padding: 10px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  line-height: 1.2;
}

.btn-primary {
  background: linear-gradient(135deg, #0284c7, #2563eb);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(2, 132, 199, 0.35);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #0369a1, #1d4ed8);
  box-shadow: 0 6px 18px rgba(2, 132, 199, 0.45);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: #ffffff;
  color: var(--text-heading);
  border-color: var(--border-color);
  box-shadow: 0 2px 6px rgba(2, 132, 199, 0.06);
}

.btn-secondary:hover {
  background-color: #f0f9ff;
  border-color: var(--primary);
  color: var(--primary);
}

.btn-lg {
  padding: 14px 28px;
  font-size: 1.1rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  min-height: 48px;
}

.btn-block {
  width: 100%;
}

/* 英雄视觉区 (Hero 晴空高照感) */
.hero-section {
  position: relative;
  padding: 72px 0 60px;
  text-align: center;
  background: radial-gradient(circle at 50% 18%, rgba(56, 189, 248, 0.28) 0%, rgba(224, 242, 254, 0) 70%);
  border-bottom: 1px solid var(--border-color);
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  border-radius: var(--radius-full);
  background: #ffffff;
  border: 1px solid #7dd3fc;
  color: #0369a1;
  font-size: 0.875rem;
  font-weight: 700;
  margin-bottom: 24px;
  box-shadow: 0 2px 8px rgba(2, 132, 199, 0.1);
}

.hero-pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--success);
}

.hero-title {
  font-size: clamp(1.85rem, 4.5vw, 3.25rem);
  font-weight: 900;
  line-height: 1.25;
  margin-bottom: 20px;
  color: var(--text-heading);
  letter-spacing: -0.02em;
}

.hero-title-highlight {
  background: linear-gradient(135deg, #0284c7, #2563eb);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: var(--text-muted);
  max-width: 820px;
  margin: 0 auto 28px;
  font-weight: 500;
  line-height: 1.7;
}

.hero-intro {
  font-size: 0.95rem;
  color: var(--text-dim);
  max-width: 720px;
  margin: 0 auto 36px;
  line-height: 1.75;
}

.hero-cta-group {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.hero-guarantee {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 500;
}

.guarantee-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.guarantee-item svg {
  color: var(--primary);
}

/* 核心板块公共样式 */
.section {
  padding: 64px 0;
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-tag {
  display: inline-block;
  color: #0369a1;
  font-size: 0.875rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.section-title {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 800;
  color: var(--text-heading);
  margin-bottom: 12px;
}

.section-desc {
  font-size: 1rem;
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto;
}

/* 套餐价格表 (纯白卡片 + 晴空蓝头部) */
.pricing-table-wrapper {
  width: 100%;
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: var(--shadow-lg);
  margin-bottom: 24px;
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.pricing-table caption {
  padding: 16px 20px;
  font-size: 1.1rem;
  font-weight: 700;
  color: #ffffff;
  background: linear-gradient(135deg, #0284c7, #0369a1);
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.pricing-table th,
.pricing-table td {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-card);
  vertical-align: middle;
}

.pricing-table thead th {
  background: #f0f9ff;
  color: #0369a1;
  font-weight: 700;
  font-size: 0.875rem;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.pricing-table tbody tr:hover {
  background-color: #f8fbff;
}

.pricing-table .featured-row {
  background-color: #f0f9ff;
}

.plan-name {
  font-weight: 700;
  color: var(--text-heading);
  font-size: 1.05rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.badge-rec {
  background: linear-gradient(135deg, #f59e0b, #d97706);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: var(--radius-full);
}

.price-val {
  font-size: 1.35rem;
  font-weight: 800;
  color: #0284c7;
}

.price-period {
  font-size: 0.85rem;
  color: var(--text-dim);
  font-weight: 400;
}

.feature-tag {
  display: inline-block;
  background: #e0f2fe;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  margin: 2px 0;
  color: #0369a1;
  font-weight: 600;
}

/* 核心优势卡片（3个图文卡片，纯白悬浮感） */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: #7dd3fc;
  box-shadow: var(--shadow-lg);
}

.feature-icon-wrapper {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: #e0f2fe;
  border: 1px solid #bae6fd;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: #0284c7;
}

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

.feature-card-desc {
  font-size: 0.925rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 16px;
}

.feature-card-list {
  list-style: none;
  margin-top: auto;
}

.feature-card-list li {
  font-size: 0.85rem;
  color: var(--text-dim);
  padding: 4px 0;
  display: flex;
  align-items: center;
  gap: 8px;
}

.feature-card-list li::before {
  content: "✓";
  color: var(--success);
  font-weight: 800;
}

/* 流媒体与AI支持卡片 */
.media-ai-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 32px;
}

.media-ai-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  box-shadow: var(--shadow-sm);
}

.media-ai-card-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 20px;
}

.media-ai-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  background: #e0f2fe;
  color: #0284c7;
}

.media-ai-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-heading);
}

.media-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.media-badge {
  background: #f0f9ff;
  border: 1px solid #bae6fd;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  color: #0369a1;
  font-weight: 600;
}

/* 用户评价区 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.review-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 24px;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
}

.review-stars {
  color: #f59e0b;
  font-size: 1rem;
  margin-bottom: 12px;
  letter-spacing: 2px;
}

.review-quote {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
  flex-grow: 1;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: auto;
  border-top: 1px solid var(--border-card);
  padding-top: 12px;
}

.review-avatar {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: #e0f2fe;
  border: 1px solid #bae6fd;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #0284c7;
  font-size: 0.85rem;
}

.review-info {
  display: flex;
  flex-direction: column;
}

.review-name {
  font-weight: 700;
  font-size: 0.875rem;
  color: var(--text-heading);
}

.review-role {
  font-size: 0.75rem;
  color: var(--text-dim);
}

/* FAQ 常见问题（默认展开） */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.faq-item:hover {
  border-color: #7dd3fc;
  box-shadow: var(--shadow-md);
}

.faq-item summary {
  padding: 18px 22px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-heading);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background-color: transparent;
}

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

.faq-item summary::after {
  content: "−";
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary);
  transition: transform 0.2s ease;
  line-height: 1;
}

.faq-item:not([open]) summary::after {
  content: "+";
}

.faq-answer {
  padding: 0 22px 20px 22px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
  border-top: 1px solid var(--border-card);
}

.faq-answer p {
  margin-top: 12px;
}

.faq-answer a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  font-weight: 600;
}

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

/* 知识科普与文章页面样式 */
.article-header {
  padding: 48px 0 32px;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
}

.breadcrumb {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.breadcrumb a {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
}

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

.article-title {
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
  font-weight: 800;
  color: var(--text-heading);
  margin-bottom: 16px;
  line-height: 1.3;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.article-content {
  max-width: 820px;
  margin: 40px auto;
  font-size: 1.025rem;
  line-height: 1.8;
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 40px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-sm);
}

.article-content h2 {
  font-size: 1.45rem;
  font-weight: 700;
  color: var(--text-heading);
  margin: 36px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-card);
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 600;
  color: #1e3a5f;
  margin: 24px 0 12px;
}

.article-content p {
  margin-bottom: 18px;
  color: var(--text-muted);
}

.article-content ul,
.article-content ol {
  margin: 0 0 20px 24px;
  color: var(--text-muted);
}

.article-content li {
  margin-bottom: 8px;
}

.article-content a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  font-weight: 600;
}

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

.article-callout {
  background: #f0f9ff;
  border-left: 4px solid var(--primary);
  padding: 18px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 24px 0;
  color: var(--text-heading);
  font-weight: 500;
}

.article-nav-box {
  background: #f8fbff;
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin: 48px auto;
  max-width: 820px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

/* 科普文章列表网格 */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin: 40px 0;
}

.article-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow-sm);
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: #7dd3fc;
  box-shadow: var(--shadow-lg);
}

.article-card-tag {
  color: #0284c7;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
  flex-grow: 1;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-dim);
  border-top: 1px solid var(--border-card);
  padding-top: 12px;
}

/* 网站地图列表 */
.sitemap-section {
  max-width: 860px;
  margin: 40px auto;
}

.sitemap-group {
  background: #ffffff;
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.sitemap-group h2 {
  font-size: 1.25rem;
  color: var(--text-heading);
  margin-bottom: 16px;
  border-bottom: 1px solid var(--border-card);
  padding-bottom: 8px;
}

.sitemap-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.sitemap-list li a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
}

.sitemap-list li a:hover {
  text-decoration: underline;
}

.sitemap-list li span {
  color: var(--text-dim);
  font-size: 0.85rem;
  margin-left: 8px;
}

/* 单独信息页面（关于我们、服务条款、隐私政策） */
.info-page-container {
  max-width: 860px;
  margin: 48px auto;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-md);
}

.info-page-container h1 {
  font-size: 2rem;
  color: var(--text-heading);
  margin-bottom: 16px;
}

.info-page-container h2 {
  font-size: 1.35rem;
  color: var(--text-heading);
  margin: 32px 0 12px;
  border-bottom: 1px solid var(--border-card);
  padding-bottom: 8px;
}

.info-page-container p {
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 16px;
}

.info-page-container ul {
  margin: 0 0 20px 24px;
  color: var(--text-muted);
}

.info-page-container li {
  margin-bottom: 8px;
  line-height: 1.7;
}

/* 页脚：严格只保留 4 个标题链接 (深邃午夜蓝底衬，形成视觉稳定锚点) */
.site-footer {
  margin-top: auto;
  background-color: #0b1728;
  border-top: 1px solid #1e3a5f;
  padding: 40px 0 32px;
  text-align: center;
}

.footer-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 32px;
  margin-bottom: 24px;
  list-style: none;
  flex-wrap: wrap;
}

.footer-nav-link {
  color: #cbd5e1;
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  padding: 8px 12px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  border-radius: var(--radius-sm);
  transition: color 0.2s ease;
}

.footer-nav-link:hover {
  color: #38bdf8;
}

.footer-copy {
  color: #64748b;
  font-size: 0.85rem;
}

/* 响应式媒体查询适配 (360px, 390px, 768px, 1440px) */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --header-height: auto;
  }
  .site-header {
    padding: 12px 0;
  }
  .header-container {
    flex-direction: column;
    gap: 12px;
  }
  .nav-menu {
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
  }
  .nav-link {
    font-size: 0.9rem;
    padding: 6px 10px;
  }
  .hero-section {
    padding: 48px 0 40px;
  }
  .hero-title {
    font-size: 1.85rem;
  }
  .hero-subtitle {
    font-size: 1.05rem;
  }
  .hero-cta-group {
    flex-direction: column;
    align-items: stretch;
    padding: 0 16px;
  }
  .btn-lg {
    width: 100%;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .media-ai-grid {
    grid-template-columns: 1fr;
  }
  .reviews-grid {
    grid-template-columns: 1fr;
  }
  .articles-grid {
    grid-template-columns: 1fr;
  }
  .footer-nav {
    flex-direction: column;
    gap: 12px;
  }
  .article-content {
    padding: 24px 16px;
  }
  .info-page-container {
    padding: 24px 16px;
  }
}

@media (max-width: 390px) {
  .container {
    padding-left: 14px;
    padding-right: 14px;
  }
  .hero-title {
    font-size: 1.65rem;
  }
  .section-title {
    font-size: 1.35rem;
  }
  .pricing-table th,
  .pricing-table td {
    padding: 12px 10px;
  }
}