/* ==========================================================================
   鹿语云机场 (Luyuyun VPN) - 官方品牌风格设计系统
   设计语言：Corporate 专业企业风格 (现代微渐变 / 极简白底 / 商务蓝 / 动态点缀)
   ========================================================================== */

:root {
  --primary: #1d68f0;
  --primary-hover: #1557d0;
  --primary-light: #eaf2ff;
  --primary-glow: rgba(29, 104, 240, 0.25);
  --accent-cyan: #00c6ff;
  --accent-green: #10b981;
  --accent-orange: #f59e0b;
  
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --bg-elevated: #ffffff;
  --bg-subtle: #f1f5f9;
  
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  
  --border-light: #e2e8f0;
  --border-hover: #cbd5e1;
  --border-active: #bfdbfe;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 25px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.04);
  --shadow-hover: 0 20px 35px -5px rgba(29, 104, 240, 0.12), 0 8px 10px -6px rgba(15, 23, 42, 0.06);
  --shadow-featured: 0 15px 35px -5px rgba(29, 104, 240, 0.22);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  --container-max: 1200px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background-color: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  position: relative;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  display: block;
}

/* 动态背景点缀装饰层 */
.bg-ambient-layer {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.ambient-blob {
  position: absolute;
  filter: blur(80px);
  border-radius: 50%;
  opacity: 0.6;
  animation: floatOrb 20s infinite alternate ease-in-out;
}

.ambient-blob-1 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(29, 104, 240, 0.12) 0%, rgba(29, 104, 240, 0) 70%);
  top: -150px;
  right: -100px;
}

.ambient-blob-2 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 198, 255, 0.08) 0%, rgba(0, 198, 255, 0) 70%);
  top: 40%;
  left: -200px;
  animation-duration: 25s;
}

.ambient-blob-3 {
  width: 450px;
  height: 450px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.08) 0%, rgba(99, 102, 241, 0) 70%);
  bottom: 5%;
  right: -100px;
}

.ambient-grid {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    linear-gradient(to right, rgba(226, 232, 240, 0.45) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(226, 232, 240, 0.45) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at center, black 40%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 40%, transparent 80%);
}

@keyframes floatOrb {
  0% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(40px, -30px) scale(1.08); }
  100% { transform: translate(-30px, 40px) scale(0.95); }
}

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* 顶部通知条 */
.top-announcement {
  background: linear-gradient(90deg, #1d68f0 0%, #2563eb 50%, #00c6ff 100%);
  color: #ffffff;
  font-size: 0.875rem;
  padding: 8px 16px;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  font-weight: 500;
  position: relative;
  z-index: 50;
}

.top-announcement a {
  text-decoration: underline;
  font-weight: 600;
  color: #fff;
  transition: opacity 0.2s;
}

.top-announcement a:hover {
  opacity: 0.9;
}

.badge-tag {
  background: rgba(255, 255, 255, 0.22);
  padding: 2px 8px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  letter-spacing: 0.5px;
}

/* 顶部导航栏 (Header) */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.8);
  transition: var(--transition);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.logo-icon {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: linear-gradient(135deg, #1d68f0 0%, #00c6ff 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-size: 1.15rem;
  box-shadow: 0 4px 10px rgba(29, 104, 240, 0.3);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
  position: relative;
  padding: 6px 2px;
}

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

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.25s ease;
  border-radius: 2px;
}

.nav-link:hover::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* 按钮设计规范 - 契合图1专业企业按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(29, 104, 240, 0.3);
}

.btn-primary:hover {
  background: var(--primary-hover);
  box-shadow: 0 6px 20px rgba(29, 104, 240, 0.45);
  transform: translateY(-1px);
}

.btn-outline {
  background: transparent;
  color: var(--text-secondary);
  border-color: var(--border-light);
}

.btn-outline:hover {
  background: #f8fafc;
  color: var(--primary);
  border-color: var(--primary);
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1.05rem;
  border-radius: 10px;
}

.btn-pulse {
  position: relative;
  overflow: hidden;
}

.btn-pulse::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.25), transparent);
  animation: shine 3s infinite;
}

@keyframes shine {
  0% { left: -100%; }
  20% { left: 100%; }
  100% { left: 100%; }
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-primary);
}

/* 模块标题与排版 */
.section-header {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 56px auto;
}

.section-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 16px;
  border: 1px solid rgba(29, 104, 240, 0.15);
}

.section-title {
  font-size: 2.3rem;
  font-weight: 800;
  letter-spacing: -0.8px;
  color: var(--text-primary);
  margin-bottom: 14px;
  line-height: 1.25;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* HERO SECTION */
.hero-section {
  padding: 80px 0 60px 0;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 50px;
  align-items: center;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(29, 104, 240, 0.08);
  border: 1px solid rgba(29, 104, 240, 0.2);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 24px;
}

.hero-pill .dot {
  width: 8px;
  height: 8px;
  background: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.2);
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -1.2px;
  color: var(--text-primary);
  margin-bottom: 22px;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #1d68f0 0%, #0099ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-description {
  font-size: 1.15rem;
  color: var(--text-secondary);
  margin-bottom: 34px;
  line-height: 1.75;
}

.hero-badges-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 36px;
}

.hero-badge-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
  box-shadow: var(--shadow-sm);
}

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

.hero-cta-group {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-guarantee {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-top: 24px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

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

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

/* HERO 右侧动态展示卡片 (Corporate 极简质感) */
.hero-visual-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-lg);
  position: relative;
  transition: var(--transition);
}

.hero-visual-card:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--border-active);
}

.card-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 20px;
}

.status-indicator {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent-green);
}

.pulse-circle {
  width: 10px;
  height: 10px;
  background-color: var(--accent-green);
  border-radius: 50%;
  animation: pulse-ring 2s infinite;
}

@keyframes pulse-ring {
  0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.5); }
  70% { box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
  100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-bottom: 20px;
}

.metric-box {
  background: var(--bg-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  border: 1px solid rgba(226, 232, 240, 0.7);
}

.metric-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}

.metric-value {
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--text-primary);
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.metric-unit {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.node-speed-live {
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 16px;
}

.node-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 0;
  font-size: 0.875rem;
  border-bottom: 1px dashed var(--border-light);
}

.node-row:last-child {
  border-bottom: none;
}

.node-name {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 500;
}

.node-ping {
  color: var(--accent-green);
  font-weight: 700;
  font-family: monospace;
}

/* 核心卖点网格 (Core Features) */
.features-section {
  padding: 80px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: var(--transition);
  position: relative;
}

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

.feature-icon-wrapper {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 22px;
  font-size: 1.5rem;
  transition: var(--transition);
}

.feature-card:hover .feature-icon-wrapper {
  background: var(--primary);
  color: #ffffff;
  transform: scale(1.08);
}

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

.feature-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* 价格套餐模块 (Pricing Section - 严格契合图2) */
.pricing-section {
  padding: 90px 0;
  background: linear-gradient(180deg, rgba(241, 245, 249, 0.5) 0%, rgba(255, 255, 255, 1) 100%);
  position: relative;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 38px 32px;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
  position: relative;
  box-shadow: var(--shadow-sm);
}

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

/* 推荐套餐卡片 (中间卡片 - 突出蓝边与吸顶标签) */
.pricing-card.featured {
  border: 2px solid var(--primary);
  box-shadow: var(--shadow-featured);
  transform: scale(1.02);
  z-index: 2;
}

.pricing-card.featured:hover {
  transform: scale(1.03) translateY(-4px);
}

.badge-featured {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: #ffffff;
  padding: 4px 18px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  box-shadow: 0 4px 10px rgba(29, 104, 240, 0.4);
}

.package-name {
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.package-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  min-height: 48px;
  margin-bottom: 24px;
  line-height: 1.5;
}

.package-price-wrap {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 28px;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--border-light);
}

.currency-symbol {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.price-number {
  font-size: 3.2rem;
  font-weight: 900;
  color: var(--text-primary);
  letter-spacing: -1.5px;
  line-height: 1;
}

.price-billing-cycle {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: 500;
}

.package-features {
  list-style: none;
  margin-bottom: 34px;
  flex-grow: 1;
}

.package-features li {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  padding: 10px 0;
  border-bottom: 1px dashed rgba(226, 232, 240, 0.6);
}

.package-features li:last-child {
  border-bottom: none;
}

.package-features li svg {
  color: #10b981;
  flex-shrink: 0;
}

.pricing-btn {
  width: 100%;
  padding: 14px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  margin-top: auto;
}

.pricing-card.featured .pricing-btn {
  background: var(--primary);
  color: #ffffff;
}

.pricing-card:not(.featured) .pricing-btn {
  background: #ffffff;
  color: var(--text-primary);
  border: 1px solid var(--border-light);
}

.pricing-card:not(.featured) .pricing-btn:hover {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

/* 快捷入口与优惠码横幅 */
.portal-banner {
  margin-top: 50px;
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 24px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
  box-shadow: var(--shadow-sm);
}

.portal-info {
  display: flex;
  align-items: center;
  gap: 18px;
}

.portal-badge {
  background: #fef3c7;
  color: #b45309;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: 0.85rem;
}

.portal-text strong {
  color: var(--text-primary);
  font-size: 1.05rem;
}

.portal-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* 全平台客户端支持 (Clients Section) */
.clients-section {
  padding: 80px 0;
}

.clients-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.client-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 26px 20px;
  text-align: center;
  transition: var(--transition);
}

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

.client-os-icon {
  width: 50px;
  height: 50px;
  margin: 0 auto 16px auto;
  border-radius: 12px;
  background: var(--bg-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
  font-size: 1.6rem;
}

.client-os-name {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.client-apps {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 18px;
}

.client-btn {
  font-size: 0.85rem;
  padding: 6px 16px;
  width: 100%;
}

/* 知识库与教程模块 (Knowledge Base) */
.kb-section {
  padding: 80px 0;
  background: #f8fafc;
}

.kb-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.kb-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

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

.kb-category {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 8px;
}

.kb-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text-primary);
}

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

.kb-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.kb-link:hover {
  text-decoration: underline;
}

/* AI工具生态加速 (AI Tools Section) */
.ai-section {
  padding: 80px 0;
}

.ai-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.ai-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 22px;
  display: flex;
  align-items: flex-start;
  gap: 14px;
  transition: var(--transition);
}

.ai-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}

.ai-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--bg-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}

.ai-meta h4 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.ai-meta p {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* 常见问题模块 (50 FAQs) */
.faq-section {
  padding: 90px 0;
  background: #ffffff;
}

.faq-search-wrapper {
  max-width: 640px;
  margin: 0 auto 32px auto;
  position: relative;
}

.faq-search-input {
  width: 100%;
  padding: 14px 20px 14px 48px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-light);
  font-size: 0.95rem;
  outline: none;
  background: #f8fafc;
  transition: var(--transition);
}

.faq-search-input:focus {
  border-color: var(--primary);
  background: #ffffff;
  box-shadow: 0 0 0 4px var(--primary-light);
}

.faq-search-icon {
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
}

.faq-category-tabs {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 40px;
}

.faq-tab-btn {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  border: 1px solid var(--border-light);
  background: #ffffff;
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
}

.faq-tab-btn.active, .faq-tab-btn:hover {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.faq-list {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  background: #ffffff;
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--border-hover);
}

.faq-question {
  width: 100%;
  padding: 18px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-align: left;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  gap: 16px;
}

.faq-question-title {
  display: flex;
  align-items: center;
  gap: 10px;
}

.faq-tag {
  font-size: 0.75rem;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.faq-toggle-icon {
  font-size: 1.25rem;
  color: var(--text-muted);
  transition: transform 0.25s ease;
}

.faq-item.active .faq-toggle-icon {
  transform: rotate(180deg);
  color: var(--primary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s ease;
  background: #fbfcfe;
}

.faq-item.active .faq-answer {
  max-height: 600px;
  padding: 0 24px 22px 24px;
  border-top: 1px solid rgba(226, 232, 240, 0.6);
}

.faq-answer-inner {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.75;
  padding-top: 14px;
}

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

/* 博客/SEO精选文章模块 (Articles Section) */
.articles-section {
  padding: 90px 0;
  background: #f8fafc;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.article-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}

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

.article-thumb {
  height: 180px;
  background: linear-gradient(135deg, #1d68f0 0%, #00c6ff 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  padding: 24px;
  position: relative;
  overflow: hidden;
}

.article-thumb-pattern {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0.15;
  background-image: radial-gradient(circle, #ffffff 1px, transparent 1px);
  background-size: 16px 16px;
}

.article-thumb-text {
  font-size: 1.25rem;
  font-weight: 800;
  text-align: center;
  position: relative;
  z-index: 1;
}

.article-body {
  padding: 26px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

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

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

.article-excerpt {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--border-light);
  padding-top: 14px;
}

.read-more {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.read-more:hover {
  gap: 8px;
}

/* 底部CTA区域 */
.cta-section {
  padding: 80px 0;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  color: #ffffff;
  position: relative;
  overflow: hidden;
}

.cta-box {
  text-align: center;
  max-width: 760px;
  margin: 0 auto;
}

.cta-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.cta-desc {
  font-size: 1.1rem;
  color: #94a3b8;
  margin-bottom: 32px;
}

/* 页脚 (Footer) */
.site-footer {
  background: #ffffff;
  border-top: 1px solid var(--border-light);
  padding: 60px 0 30px 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 40px;
  margin-bottom: 50px;
}

.footer-brand p {
  margin-top: 14px;
  font-size: 0.9rem;
  color: var(--text-muted);
  max-width: 320px;
  line-height: 1.7;
}

.footer-col h5 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 18px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

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

.footer-bottom {
  border-top: 1px solid var(--border-light);
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* 文章详情页专用样式 (Article Single Page Layout) */
.article-header-section {
  padding: 60px 0 30px 0;
  background: #ffffff;
  border-bottom: 1px solid var(--border-light);
}

.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

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

.article-page-title {
  font-size: 2.6rem;
  font-weight: 900;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: 18px;
  letter-spacing: -0.8px;
}

.article-page-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.article-container {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 48px;
  padding: 50px 0 80px 0;
}

.article-content {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 44px;
  box-shadow: var(--shadow-sm);
  font-size: 1.05rem;
  color: #334155;
  line-height: 1.85;
}

.article-content h2 {
  font-size: 1.7rem;
  font-weight: 800;
  color: var(--text-primary);
  margin: 38px 0 16px 0;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border-light);
}

.article-content h3 {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 26px 0 12px 0;
}

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

.article-content ul, .article-content ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

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

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

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 28px 0;
  font-size: 0.95rem;
}

.article-content th, .article-content td {
  padding: 12px 16px;
  border: 1px solid var(--border-light);
  text-align: left;
}

.article-content th {
  background: var(--bg-subtle);
  font-weight: 700;
  color: var(--text-primary);
}

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

.article-faq-box {
  margin-top: 50px;
  padding-top: 36px;
  border-top: 2px dashed var(--border-light);
}

.article-faq-title {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 24px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.article-sidebar {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.sidebar-widget {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.sidebar-widget-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-light);
}

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

.sidebar-articles-list li a {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
  display: block;
}

.sidebar-articles-list li a:hover {
  color: var(--primary);
}

/* 响应式适配 */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }
  .pricing-card.featured {
    transform: none;
  }
  .clients-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .kb-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .ai-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .article-container {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    background: #ffffff;
    flex-direction: column;
    padding: 20px;
    border-bottom: 1px solid var(--border-light);
    box-shadow: var(--shadow-lg);
  }
  .nav-menu.show {
    display: flex;
  }
  .menu-toggle {
    display: block;
  }
  .hero-title {
    font-size: 2.2rem;
  }
  .features-grid, .kb-grid, .clients-grid, .ai-grid, .articles-grid {
    grid-template-columns: 1fr;
  }
  .article-content {
    padding: 24px;
  }
  .article-page-title {
    font-size: 1.85rem;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}