/* ==========================================================================
   九云机场官网 (9-cloud.best) 核心通用样式表
   极简原生 CSS，零外部依赖，极速秒开
   【极白极简现代商务风格】
   ========================================================================== */

:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --accent: #0284c7;
  --accent-gradient: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
  --bg-main: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fafc;
  --bg-subtle: #f8fafc;
  --bg-table-stripe: #f8fafc;
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-dim: #64748b;
  --border: #e2e8f0;
  --border-focus: #2563eb;
  --success: #059669;
  --warning: #d97706;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.05), 0 1px 2px 0 rgba(0, 0, 0, 0.03);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.06), 0 2px 4px -2px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  --shadow-glow: 0 10px 25px -5px rgba(37, 99, 235, 0.15);
  --max-width: 1200px;
  --header-height: 72px;
}

/* 基础重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-main);
  background-color: var(--bg-main);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-color: var(--bg-main);
  color: var(--text-main);
}

/* 无障碍跳转 */
.skip-link {
  position: absolute;
  top: -9999px;
  left: 1rem;
  background: var(--primary);
  color: #ffffff;
  padding: 0.75rem 1.25rem;
  z-index: 9999;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
}

.skip-link:focus {
  top: 1rem;
  outline: 3px solid #0f172a;
}

/* 焦点高亮 */
:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 3px;
}

/* 排版与标题 */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-main);
  font-weight: 700;
  line-height: 1.3;
  scroll-margin-top: calc(var(--header-height) + 1.5rem);
}

h1 { font-size: 2.25rem; margin-bottom: 1rem; }
h2 { font-size: 1.75rem; margin-bottom: 0.75rem; }
h3 { font-size: 1.25rem; margin-bottom: 0.5rem; }

p {
  color: var(--text-muted);
  margin-bottom: 1rem;
}

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

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

img, svg {
  display: block;
  max-width: 100%;
  height: auto;
}

ul, ol {
  padding-left: 1.5rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

li {
  margin-bottom: 0.5rem;
}

/* 布局容器 */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.section {
  padding: 4.5rem 0;
  border-bottom: 1px solid var(--border);
  background-color: var(--bg-main);
}

.section-title-wrap {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 3rem auto;
}

.section-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--primary);
  background: var(--primary-light);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: 9999px;
  margin-bottom: 0.75rem;
}

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

/* 顶部导航栏 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: var(--header-height);
  display: flex;
  align-items: center;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-main);
  font-size: 1.375rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand-icon {
  width: 34px;
  height: 34px;
  border-radius: 9px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.22);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.brand-logo:hover .brand-icon {
  transform: scale(1.06);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.35);
}

.brand-icon svg,
.brand-icon img {
  width: 100%;
  height: 100%;
  display: block;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
}

.nav-link {
  color: var(--text-muted);
  font-size: 0.9375rem;
  font-weight: 500;
  padding: 0.5rem 0.25rem;
  transition: color 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  font-weight: 600;
}

.nav-badge-pill {
  background: var(--primary);
  color: #ffffff;
  font-size: 0.7rem;
  padding: 0.15rem 0.45rem;
  border-radius: 9999px;
  margin-left: 0.25rem;
  font-weight: 700;
}

.header-cta {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* 按钮通用体系 (保证触摸区域 >= 44x44px) */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  min-width: 44px;
  padding: 0.625rem 1.5rem;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s ease;
  line-height: 1;
  text-align: center;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #1d4ed8 0%, #0891b2 100%);
  color: #ffffff;
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: #ffffff;
  color: var(--text-main);
  border-color: #cbd5e1;
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--bg-subtle);
  border-color: #94a3b8;
  color: var(--primary);
}

.btn-sm {
  min-height: 40px;
  padding: 0.45rem 1rem;
  font-size: 0.875rem;
}

.btn-lg {
  min-height: 50px;
  padding: 0.875rem 2rem;
  font-size: 1.0625rem;
  border-radius: var(--radius-md);
}

.btn-block {
  width: 100%;
}

/* 主视觉 Hero 区域 (极白清爽高光) */
.hero-section {
  padding: 5rem 0 4.5rem 0;
  text-align: center;
  position: relative;
  background: radial-gradient(circle at 50% 15%, rgba(37, 99, 235, 0.06) 0%, rgba(255, 255, 255, 0) 70%);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 1rem;
  background: var(--primary-light);
  border: 1px solid rgba(59, 130, 246, 0.25);
  border-radius: 9999px;
  color: var(--primary);
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
}

.hero-headline {
  font-size: 3rem;
  letter-spacing: -0.03em;
  margin-bottom: 1.25rem;
  background: linear-gradient(180deg, #0f172a 0%, #334155 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subheadline {
  font-size: 1.35rem;
  color: var(--accent);
  margin-bottom: 1.25rem;
  font-weight: 600;
}

.hero-intro {
  font-size: 1.125rem;
  max-width: 780px;
  margin: 0 auto 2.25rem auto;
  line-height: 1.7;
  color: var(--text-muted);
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  max-width: 900px;
  margin: 2.5rem auto 0 auto;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

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

.stat-value {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text-main);
  display: block;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-dim);
}

/* 核心优势卡片 */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  position: relative;
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(37, 99, 235, 0.4);
  box-shadow: var(--shadow-lg);
}

.card-icon {
  width: 52px;
  height: 52px;
  background: var(--primary-light);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
  color: var(--primary);
}

.card-title {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
  color: var(--text-main);
}

.card-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
  margin-bottom: 1.25rem;
}

.card-points {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
  font-size: 0.875rem;
}

.card-points li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
  color: var(--text-muted);
}

.check-icon {
  color: var(--success);
  flex-shrink: 0;
  font-weight: bold;
}

/* 套餐价格对比表 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-bottom: 3rem;
}

.pricing-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all 0.2s ease;
}

.pricing-card.featured {
  border-color: var(--primary);
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.04) 0%, #ffffff 100%);
  box-shadow: 0 10px 25px -5px rgba(37, 99, 235, 0.15);
  transform: scale(1.03);
  z-index: 2;
}

.pricing-badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent-gradient);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.pricing-header {
  text-align: center;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1.5rem;
}

.plan-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.plan-desc {
  font-size: 0.85rem;
  color: var(--text-dim);
  min-height: 2.4em;
}

.plan-price-wrap {
  margin: 1rem 0;
}

.currency {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-main);
  vertical-align: top;
}

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

.period {
  font-size: 0.875rem;
  color: var(--text-dim);
}

.plan-features {
  list-style: none;
  padding-left: 0;
  margin-bottom: 2rem;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

/* 套餐明细表格容器 (支持横向滑动并保留语义) */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-top: 2rem;
  background-color: var(--bg-card);
  box-shadow: var(--shadow-sm);
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9375rem;
  min-width: 680px;
}

.pricing-table caption {
  padding: 1rem 1.25rem;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  background-color: var(--bg-subtle);
  caption-side: top;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.pricing-table th,
.pricing-table td {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border);
}

.pricing-table th {
  background-color: #f1f5f9;
  color: var(--text-main);
  font-weight: 600;
}

.pricing-table tbody tr:hover {
  background-color: rgba(37, 99, 235, 0.04);
}

.pricing-table td:first-child {
  font-weight: 600;
  color: var(--text-main);
}

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

.feature-media-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
}

.badges-flow {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 1.25rem 0 1.5rem 0;
}

.pill-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: var(--bg-subtle);
  border: 1px solid var(--border);
  padding: 0.4rem 0.85rem;
  border-radius: 9999px;
  font-size: 0.85rem;
  color: #1e293b;
  font-weight: 500;
}

.pill-badge svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
}

/* 用户评价区 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.review-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 0.75rem;
  font-size: 1.1rem;
  letter-spacing: 2px;
}

.review-text {
  font-size: 0.9375rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.reviewer-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  border-top: 1px solid var(--border);
  padding-top: 1rem;
}

.reviewer-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent-gradient);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
}

.reviewer-name {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-main);
}

.reviewer-role {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* FAQ 常见问题 (默认原生展开，零JS) */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 880px;
  margin: 0 auto;
}

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

.faq-item[open] {
  border-color: rgba(37, 99, 235, 0.4);
}

.faq-summary {
  padding: 1.25rem 1.5rem;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  background-color: #ffffff;
}

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

.faq-summary::after {
  content: "+";
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--primary);
  transition: transform 0.2s ease;
  margin-left: 1rem;
}

.faq-item[open] .faq-summary::after {
  content: "−";
  transform: rotate(0deg);
}

.faq-content {
  padding: 0 1.5rem 1.25rem 1.5rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
  border-top: 1px solid var(--border);
  margin-top: 0.25rem;
  padding-top: 1rem;
  background-color: #ffffff;
}

.faq-content a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 底部 CTA 区域 */
.cta-banner-section {
  border-bottom: none;
  background: radial-gradient(circle at 50% 100%, rgba(37, 99, 235, 0.08) 0%, rgba(255, 255, 255, 0) 70%);
  padding: 5rem 0;
  text-align: center;
}

/* 文章详情页与知识库通用样式 */
.article-header {
  padding: 3.5rem 0 2rem 0;
  text-align: center;
  border-bottom: 1px solid var(--border);
  background: radial-gradient(circle at 50% 0%, rgba(37, 99, 235, 0.05) 0%, rgba(255, 255, 255, 0) 70%);
}

.breadcrumbs {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-dim);
  margin-bottom: 1.5rem;
  list-style: none;
  padding-left: 0;
}

.breadcrumbs a {
  color: var(--text-muted);
}

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

.breadcrumbs li + li::before {
  content: "/";
  margin-right: 0.5rem;
  color: var(--text-dim);
}

.article-title {
  font-size: 2.25rem;
  max-width: 900px;
  margin: 0 auto 1.25rem auto;
  line-height: 1.35;
  color: var(--text-main);
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  font-size: 0.875rem;
  color: var(--text-dim);
  flex-wrap: wrap;
}

.article-meta span {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.article-body {
  max-width: 820px;
  margin: 3rem auto;
  font-size: 1.05rem;
  line-height: 1.8;
  color: #334155;
}

.article-body h2 {
  font-size: 1.6rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-main);
}

.article-body h3 {
  font-size: 1.25rem;
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
  color: var(--primary);
}

.article-body p {
  margin-bottom: 1.4rem;
  color: #334155;
}

.article-body ul, .article-body ol {
  margin-bottom: 1.5rem;
  padding-left: 2rem;
  color: #334155;
}

.article-body strong {
  color: var(--text-main);
}

.article-callout {
  background-color: var(--primary-light);
  border-left: 4px solid var(--primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 1.25rem 1.5rem;
  margin: 2rem 0;
  color: #1e3a8a;
}

.article-cta-box {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.05) 0%, rgba(6, 182, 212, 0.05) 100%);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  text-align: center;
  margin: 3.5rem 0;
}

.article-cta-box h3 {
  font-size: 1.5rem;
  color: var(--text-main);
  margin-bottom: 0.75rem;
}

.article-cta-box p {
  max-width: 580px;
  margin: 0 auto 1.5rem auto;
  color: var(--text-muted);
}

/* 知识库列表卡片 */
.knowledge-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
  margin-bottom: 3rem;
}

.knowledge-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
}

.knowledge-card:hover {
  transform: translateY(-3px);
  border-color: rgba(37, 99, 235, 0.4);
  box-shadow: var(--shadow-lg);
}

.knowledge-card-tag {
  font-size: 0.75rem;
  color: var(--primary);
  background: var(--primary-light);
  padding: 0.2rem 0.6rem;
  border-radius: 9999px;
  align-self: flex-start;
  margin-bottom: 0.85rem;
  font-weight: 600;
}

.knowledge-card-title {
  font-size: 1.15rem;
  color: var(--text-main);
  margin-bottom: 0.75rem;
  line-height: 1.4;
}

.knowledge-card-title a {
  color: var(--text-main);
}

.knowledge-card-title a:hover {
  color: var(--primary);
}

.knowledge-card-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

/* 页脚区域 (极白商务淡底色，只保留四个新页面跳转链接) */
.site-footer {
  background-color: #f8fafc;
  border-top: 1px solid var(--border);
  padding: 3.5rem 0 2rem 0;
  margin-top: auto;
}

.footer-top {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  margin-bottom: 2.5rem;
}

.footer-brand {
  margin-bottom: 1rem;
}

.footer-brand .brand-logo {
  justify-content: center;
}

.footer-tagline {
  color: var(--text-dim);
  font-size: 0.9375rem;
  max-width: 520px;
  margin: 0 auto;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.5rem;
  list-style: none;
  padding-left: 0;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

.footer-nav-link {
  color: var(--text-muted);
  font-size: 1rem;
  font-weight: 500;
  transition: color 0.2s ease;
  padding: 0.5rem 0.25rem;
}

.footer-nav-link:hover {
  color: var(--primary);
}

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 2rem;
  text-align: center;
  font-size: 0.8125rem;
  color: var(--text-dim);
}

/* 响应式媒体查询适配 */
@media (max-width: 1024px) {
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-card.featured {
    transform: none;
  }
  .grid-3, .knowledge-grid, .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --header-height: 64px;
  }
  .hero-headline {
    font-size: 2.15rem;
  }
  .hero-subheadline {
    font-size: 1.15rem;
  }
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 1.25rem;
  }
  .grid-3, .grid-2, .pricing-grid, .knowledge-grid, .reviews-grid {
    grid-template-columns: 1fr;
  }
  .main-nav {
    display: none;
  }
  .footer-nav {
    gap: 1.5rem;
  }
  .section {
    padding: 3rem 0;
  }
}

@media (max-width: 480px) {
  .hero-headline {
    font-size: 1.85rem;
  }
  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta-group .btn {
    width: 100%;
  }
  .pricing-table th, .pricing-table td {
    padding: 0.75rem 0.85rem;
  }
}

/* 无障碍偏好设置：减弱动态效果 */
@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;
  }
}