/* ==========================================================================
   一元机场 · 极速晴空 视觉系统
   极简纯原生 CSS - 秒开级极致性能，无任何外部库依赖
   ========================================================================== */

:root {
  /* 极速晴空配色系统 */
  --sky-50: #f0f9ff;
  --sky-100: #e0f2fe;
  --sky-200: #bae6fd;
  --sky-300: #7dd3fc;
  --sky-400: #38bdf8;
  --sky-500: #0ea5e9;
  --sky-600: #0284c7;
  --sky-700: #0369a1;
  --sky-800: #075985;
  --sky-900: #0c4a6e;
  
  --deep-slate: #0b1329;
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-light: #64748b;
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --border-light: #e2e8f0;
  --border-focus: #38bdf8;

  --accent-cyan: #06b6d4;
  --accent-blue: #2563eb;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;

  --gradient-sky: linear-gradient(135deg, #0ea5e9 0%, #0284c7 50%, #2563eb 100%);
  --gradient-sky-light: linear-gradient(180deg, #f0f9ff 0%, #ffffff 100%);
  --gradient-glow: radial-gradient(circle at 50% 0%, rgba(56, 189, 248, 0.15), transparent 70%);

  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 20px -2px rgba(14, 165, 233, 0.12), 0 2px 6px -1px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 12px 32px -4px rgba(14, 165, 233, 0.18), 0 4px 12px -2px rgba(15, 23, 42, 0.06);
  --shadow-cta: 0 8px 24px -4px rgba(2, 132, 199, 0.45);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --transition-fast: 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-family: var(--font-family);
  scroll-behavior: smooth;
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background: var(--bg-main);
  background-image: 
    radial-gradient(at 0% 0%, rgba(56, 189, 248, 0.12) 0px, transparent 50%),
    radial-gradient(at 100% 0%, rgba(14, 165, 233, 0.10) 0px, transparent 50%),
    radial-gradient(at 50% 50%, rgba(224, 242, 254, 0.4) 0px, transparent 80%);
  background-attachment: fixed;
}

/* 容器定义 */
.container {
  width: 100%;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* 顶栏导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 900;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.85);
  box-shadow: 0 2px 10px rgba(15, 23, 42, 0.03);
  transition: all var(--transition-fast);
}

.site-header .header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
  gap: 16px;
}

/* 左上角交互式 Logo */
.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--sky-900);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  cursor: pointer;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: transform var(--transition-fast), background-color var(--transition-fast);
  user-select: none;
  flex-shrink: 0;
}

.site-logo:hover {
  transform: translateY(-2px);
  background-color: var(--sky-50);
}

.site-logo:active {
  transform: scale(0.95);
}

.logo-icon-wrap {
  width: 38px;
  height: 38px;
  border-radius: 11px;
  background: var(--gradient-sky);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  box-shadow: 0 4px 14px rgba(14, 165, 233, 0.4);
  transition: transform 0.4s ease;
}

.site-logo:hover .logo-icon-wrap {
  transform: rotate(-12deg) scale(1.08);
}

.site-logo.fly-up .logo-icon-wrap {
  animation: planeTakeoff 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes planeTakeoff {
  0% { transform: translateY(0) scale(1); }
  40% { transform: translateY(-8px) scale(1.2) rotate(-15deg); }
  100% { transform: translateY(0) scale(1); }
}

.logo-badge {
  font-size: 0.75rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--sky-100) 0%, #dbeafe 100%);
  color: var(--sky-700);
  padding: 3px 9px;
  border-radius: var(--radius-full);
  border: 1px solid var(--sky-200);
  margin-left: 2px;
}

/* 页眉全景导航目录 */
.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: nowrap;
}

.nav-item {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 600;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background-color var(--transition-fast);
  white-space: nowrap;
}

.nav-item:hover {
  color: var(--sky-600);
  background-color: var(--sky-50);
}

.nav-item-highlight {
  color: var(--accent-blue);
  background: rgba(37, 99, 235, 0.08);
}

.nav-item-highlight:hover {
  color: var(--sky-700);
  background: rgba(37, 99, 235, 0.15);
}

/* CTA 按钮基础规范 */
.btn-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--gradient-sky);
  color: #ffffff !important;
  text-decoration: none;
  font-weight: 600;
  border-radius: var(--radius-full);
  padding: 12px 28px;
  font-size: 1rem;
  box-shadow: var(--shadow-cta);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), filter var(--transition-fast);
  cursor: pointer;
  border: none;
  outline: none;
}

.btn-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px -4px rgba(2, 132, 199, 0.55);
  filter: brightness(1.04);
}

.btn-cta:active {
  transform: translateY(1px);
}

.btn-cta-sm {
  padding: 8px 18px;
  font-size: 0.88rem;
}

.btn-cta-lg {
  padding: 16px 36px;
  font-size: 1.15rem;
  font-weight: 700;
}

.btn-secondary {
  background: #ffffff;
  color: var(--sky-700) !important;
  border: 1px solid var(--sky-300);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: var(--sky-50);
  border-color: var(--sky-400);
  box-shadow: var(--shadow-md);
}

.btn-recommend {
  background: linear-gradient(135deg, #0284c7 0%, #0369a1 40%, #1e40af 100%);
  color: #ffffff !important;
  border: 1px solid rgba(255, 255, 255, 0.3);
  box-shadow: 0 8px 24px -4px rgba(2, 132, 199, 0.45);
}

.btn-recommend:hover {
  background: linear-gradient(135deg, #0369a1 0%, #0284c7 50%, #2563eb 100%);
  box-shadow: 0 12px 28px -4px rgba(30, 64, 175, 0.55);
}

/* 章节通用结构 */
.page-section {
  padding: 80px 0;
  position: relative;
  scroll-margin-top: 70px;
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 52px;
}

.section-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 14px;
  border-radius: var(--radius-full);
  background: var(--sky-100);
  color: var(--sky-700);
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border: 1px solid var(--sky-200);
}

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

.section-desc {
  font-size: 1.1rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 1. 主视觉区 (Hero Split Layout) */
.hero-section {
  padding: 70px 0 60px;
  position: relative;
}

.hero-split-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.hero-text-col {
  text-align: left;
}

.hero-visual-col {
  position: relative;
}

.hero-badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: #ffffff;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--sky-700);
  border: 1px solid var(--sky-200);
  box-shadow: var(--shadow-sm);
  margin-bottom: 22px;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent-emerald);
  box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
  animation: pulseGreen 1.8s infinite;
}

@keyframes pulseGreen {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -0.03em;
  color: var(--deep-slate);
  margin-bottom: 20px;
}

.text-gradient-sky {
  background: linear-gradient(120deg, #0284c7 0%, #0ea5e9 40%, #06b6d4 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 0 32px 0;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.hero-meta {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 22px;
  flex-wrap: wrap;
  padding-top: 18px;
  border-top: 1px dashed var(--sky-200);
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 0.88rem;
  color: var(--text-muted);
  font-weight: 500;
}

.meta-icon {
  width: 17px;
  height: 17px;
  color: var(--sky-600);
}

/* 主视觉动态图卡 (Hero Dynamic Visual Card) */
.hero-dynamic-card {
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(56, 189, 248, 0.35);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: 0 20px 45px -10px rgba(14, 165, 233, 0.22), 0 8px 16px -4px rgba(15, 23, 42, 0.05);
  position: relative;
  transition: transform var(--transition-normal);
}

.hero-dynamic-card:hover {
  transform: translateY(-4px);
  border-color: var(--sky-400);
}

.dynamic-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--sky-100);
  margin-bottom: 18px;
}

.card-status-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--deep-slate);
}

.status-live-pill {
  font-size: 0.75rem;
  font-weight: 700;
  background: rgba(16, 185, 129, 0.12);
  color: #059669;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  gap: 6px;
  border: 1px solid rgba(16, 185, 129, 0.25);
}

/* 动态下行速率看板 */
.speed-meter-box {
  background: linear-gradient(135deg, #0c4a6e 0%, #0369a1 60%, #0284c7 100%);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  color: #ffffff;
  margin-bottom: 18px;
  box-shadow: 0 8px 20px -4px rgba(2, 132, 199, 0.4);
  position: relative;
  overflow: hidden;
}

.speed-meter-box::after {
  content: "";
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.15) 0%, transparent 60%);
  animation: rotateLight 10s linear infinite;
  pointer-events: none;
}

@keyframes rotateLight {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.speed-meter-label {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  opacity: 0.85;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.speed-meter-val {
  font-size: 2.1rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  margin: 6px 0 2px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.speed-meter-val small {
  font-size: 1rem;
  font-weight: 600;
  opacity: 0.9;
}

.speed-wave-svg {
  width: 100%;
  height: 38px;
  display: block;
}

/* 节点实时延迟雷达监控列表 */
.nodes-monitor-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.node-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  background: var(--sky-50);
  border: 1px solid var(--sky-100);
  font-size: 0.85rem;
  transition: all var(--transition-fast);
}

.node-row:hover {
  background: #ffffff;
  border-color: var(--sky-300);
  transform: translateX(4px);
}

.node-info-left {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  color: var(--deep-slate);
}

.node-flag {
  font-size: 1.1rem;
  line-height: 1;
}

.node-info-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.node-ping-val {
  font-weight: 700;
  color: #059669;
  font-family: monospace;
  font-size: 0.88rem;
}

.node-tag-pill {
  font-size: 0.72rem;
  background: var(--sky-100);
  color: var(--sky-700);
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
}

/* 浮动漂浮徽章 (Floating Badges) */
.floating-badge {
  position: absolute;
  padding: 8px 14px;
  border-radius: var(--radius-full);
  background: #ffffff;
  box-shadow: 0 10px 25px -4px rgba(15, 23, 42, 0.15), 0 2px 8px rgba(14, 165, 233, 0.12);
  border: 1px solid var(--sky-200);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--deep-slate);
  display: flex;
  align-items: center;
  gap: 6px;
  z-index: 10;
  pointer-events: none;
}

.badge-float-1 {
  top: -16px;
  right: -12px;
  animation: floatSlow 3.8s ease-in-out infinite alternate;
}

.badge-float-2 {
  bottom: -14px;
  left: -14px;
  animation: floatSlow 4.2s ease-in-out infinite alternate-reverse;
}

@keyframes floatSlow {
  0% { transform: translateY(0px) rotate(0deg); }
  100% { transform: translateY(-8px) rotate(2deg); }
}

/* 2. 核心优势卡片 (3 Cards) */
.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: 36px 30px;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-sky);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--sky-300);
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon-box {
  width: 60px;
  height: 60px;
  border-radius: 16px;
  background: var(--sky-100);
  color: var(--sky-600);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  transition: transform var(--transition-fast), background-color var(--transition-fast), color var(--transition-fast);
}

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

.feature-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--deep-slate);
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.98rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 20px;
}

.feature-specs {
  list-style: none;
  border-top: 1px solid var(--sky-100);
  padding-top: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.feature-specs li {
  font-size: 0.88rem;
  color: var(--text-light);
  display: flex;
  align-items: center;
  gap: 8px;
}

.spec-check {
  color: var(--sky-600);
  font-weight: bold;
}

/* 3. 流媒体与 AI 支持图卡 */
.media-ai-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
}

.unlock-box {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
  padding: 36px 32px;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.unlock-box:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--sky-300);
}

.unlock-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
}

.unlock-icon-circle {
  width: 48px;
  height: 48px;
  border-radius: 14px;
  background: var(--sky-100);
  color: var(--sky-700);
  display: flex;
  align-items: center;
  justify-content: center;
}

.unlock-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--deep-slate);
}

.unlock-subtitle {
  font-size: 0.88rem;
  color: var(--text-light);
}

.unlock-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 24px;
}

.apps-chip-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.app-chip {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 11px 14px;
  background: #ffffff;
  border: 1px solid var(--sky-200);
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--deep-slate);
  transition: all var(--transition-fast);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

.app-chip:hover {
  background: var(--sky-50);
  border-color: var(--sky-400);
  box-shadow: 0 4px 14px rgba(14, 165, 233, 0.15);
  transform: translateY(-2px);
}

.app-chip-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-icon-svg {
  width: 22px;
  height: 22px;
  flex-shrink: 0;
}

.app-tag-badge {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 4px;
  background: var(--sky-100);
  color: var(--sky-700);
  white-space: nowrap;
}

.chip-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-emerald);
}

.network-speed-bar {
  margin-top: 24px;
  padding: 16px;
  background: linear-gradient(135deg, rgba(240, 249, 255, 0.8) 0%, rgba(224, 242, 254, 0.5) 100%);
  border-radius: var(--radius-md);
  border: 1px dashed var(--sky-300);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.88rem;
}

.speed-metric {
  font-weight: 700;
  color: var(--sky-700);
}

/* 4. 套餐价格对比表 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
  padding: 38px 28px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.pricing-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.pricing-card.featured {
  border: 2px solid var(--sky-500);
  box-shadow: var(--shadow-md);
  background: linear-gradient(180deg, #ffffff 0%, #f0f9ff 100%);
  transform: scale(1.03);
}

.pricing-card.featured:hover {
  transform: scale(1.03) translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-sky);
  color: #ffffff;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: var(--radius-full);
  box-shadow: 0 4px 10px rgba(14, 165, 233, 0.35);
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.plan-header {
  text-align: center;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--sky-100);
  margin-bottom: 24px;
}

.plan-name {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--deep-slate);
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 0.88rem;
  color: var(--text-light);
  min-height: 40px;
}

.plan-price-wrap {
  margin: 16px 0 6px;
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 2px;
}

.price-currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--sky-700);
}

.price-num {
  font-size: 3.2rem;
  font-weight: 900;
  color: var(--deep-slate);
  line-height: 1;
}

.price-period {
  font-size: 0.92rem;
  color: var(--text-light);
  font-weight: 500;
}

.plan-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.92rem;
  color: var(--text-muted);
}

.check-icon {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--sky-100);
  color: var(--sky-600);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: bold;
  flex-shrink: 0;
}

.pricing-card .btn-cta {
  width: 100%;
}

/* 5. 用户评价 (Testimonials) */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
}

.review-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.review-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--sky-300);
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 16px;
  letter-spacing: 2px;
  font-size: 1.05rem;
}

.review-content {
  font-size: 0.96rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 22px;
  font-style: italic;
}

.reviewer-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--sky-100);
  padding-top: 16px;
}

.reviewer-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--sky-100);
  color: var(--sky-700);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
  border: 2px solid #ffffff;
  box-shadow: 0 2px 6px rgba(14, 165, 233, 0.2);
}

.reviewer-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--deep-slate);
}

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

/* 6. 常见问题解答 (FAQ) */
.faq-wrap {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

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

.faq-item:hover {
  border-color: var(--sky-300);
}

.faq-question {
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--deep-slate);
  user-select: none;
}

.faq-toggle-icon {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--sky-600);
  transition: transform var(--transition-fast);
  font-size: 1.2rem;
  font-weight: bold;
}

.faq-item.active .faq-toggle-icon {
  transform: rotate(45deg);
  color: var(--sky-700);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0.16, 1, 0.3, 1), padding 0.3s ease;
  padding: 0 24px;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
  background: var(--sky-50);
}

.faq-item.active .faq-answer {
  max-height: 300px;
  padding: 0 24px 20px 24px;
}

/* 7. 底栏 (Footer) 仅保留4个标题，打开新页面展示 */
.site-footer {
  background: #ffffff;
  border-top: 1px solid var(--border-light);
  padding: 50px 0 40px;
  position: relative;
  text-align: center;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 36px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.footer-link {
  color: var(--deep-slate);
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 600;
  position: relative;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.footer-link:hover {
  color: var(--sky-600);
  background-color: var(--sky-50);
}

/* 页脚 SEO 权重关键词集群 (PBN Dofollow Cluster) */
.footer-seo-tags {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin: 18px auto 20px;
  max-width: 960px;
  padding: 12px 18px;
  background: var(--sky-50);
  border: 1px solid var(--sky-100);
  border-radius: var(--radius-md);
  font-size: 0.85rem;
}

.seo-tags-label {
  font-weight: 700;
  color: var(--sky-800);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.seo-tag-link {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
  transition: all var(--transition-fast);
}

.seo-tag-link:hover {
  color: var(--sky-600);
  text-decoration: underline;
  transform: translateY(-1px);
}

.seo-tag-sep {
  color: var(--sky-200);
  font-size: 0.75rem;
  user-select: none;
}

/* 页脚安全与高可用保障微徽章 */
.footer-trust-badges {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  flex-wrap: wrap;
  margin: 16px auto;
  max-width: 900px;
}

.trust-badge-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
  color: var(--text-light);
  font-weight: 500;
}

.trust-badge-item svg {
  color: var(--sky-600);
  flex-shrink: 0;
}

/* 合规免责声明 */
.footer-disclaimer {
  max-width: 820px;
  margin: 14px auto 16px;
  font-size: 0.78rem;
  color: #94a3b8;
  line-height: 1.6;
}

/* 友情链接与主博客矩阵外链声明 */
.footer-friend-links {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin: 12px auto 14px;
  font-size: 0.85rem;
  color: var(--text-light);
}

.friend-link-item {
  color: var(--sky-700);
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.friend-link-item:hover {
  color: var(--sky-500);
  text-decoration: underline;
  transform: translateY(-1px);
}

.friend-link-sep {
  color: var(--sky-300);
  user-select: none;
}

.footer-copy {
  font-size: 0.85rem;
  color: var(--text-light);
}

/* ==========================================================================
   右侧章节切换浮动控制器 (Section Arrow Navigator)
   ========================================================================== */
.section-nav-controller {
  position: fixed;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 12px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 10px 8px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(226, 232, 240, 0.9);
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.12);
}

.nav-arrow-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--sky-200);
  background: #ffffff;
  color: var(--sky-600);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.nav-arrow-btn:hover {
  background: var(--gradient-sky);
  color: #ffffff;
  border-color: transparent;
  transform: scale(1.1);
  box-shadow: 0 4px 14px rgba(14, 165, 233, 0.4);
}

.nav-arrow-btn:active {
  transform: scale(0.92);
}

.nav-arrow-btn.disabled {
  opacity: 0.4;
  cursor: not-allowed;
  pointer-events: none;
}

.nav-progress-dots {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 4px 0;
}

.nav-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--sky-200);
  transition: all var(--transition-fast);
  cursor: pointer;
}

.nav-dot.active {
  height: 16px;
  border-radius: 4px;
  background: var(--sky-600);
}

/* ==========================================================================
   二级页面专属样式 (关于我们、服务条款、隐私政策、网站地图)
   ========================================================================== */
.subpage-hero {
  padding: 60px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--sky-100);
  background: linear-gradient(180deg, var(--sky-50) 0%, #ffffff 100%);
}

.subpage-content {
  max-width: 860px;
  margin: 50px auto 80px;
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow-sm);
}

.subpage-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--deep-slate);
  margin-top: 32px;
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--sky-100);
}

.subpage-content h2:first-of-type {
  margin-top: 0;
}

.subpage-content p {
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 16px;
  font-size: 1rem;
}

.subpage-content ul {
  margin-left: 20px;
  margin-bottom: 20px;
  color: var(--text-muted);
  line-height: 1.75;
}

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

.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 24px;
}

.sitemap-card {
  padding: 24px;
  background: var(--sky-50);
  border: 1px solid var(--sky-200);
  border-radius: var(--radius-md);
}

.sitemap-card h3 {
  font-size: 1.15rem;
  color: var(--sky-800);
  margin-bottom: 12px;
}

/* ==========================================================================
   文章专栏与图卡列表样式 (SEO Articles Section & Cards)
   ========================================================================== */
.articles-section {
  padding: 80px 0;
  position: relative;
  background: linear-gradient(180deg, rgba(240, 249, 255, 0.6) 0%, #ffffff 100%);
  scroll-margin-top: 70px;
}

.article-filter-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.filter-btn {
  background: #ffffff;
  border: 1px solid var(--sky-200);
  border-radius: var(--radius-full);
  padding: 8px 18px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
  outline: none;
}

.filter-btn:hover {
  border-color: var(--sky-400);
  color: var(--sky-700);
  background: var(--sky-50);
}

.filter-btn.active {
  background: var(--gradient-sky);
  color: #ffffff;
  border-color: transparent;
  box-shadow: 0 4px 12px rgba(14, 165, 233, 0.35);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
  margin-top: 24px;
}

.article-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 26px 24px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  text-decoration: none;
  color: inherit;
  position: relative;
  overflow: hidden;
}

.article-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-sky);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.article-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  border-color: var(--sky-300);
}

.article-card:hover::before {
  opacity: 1;
}

.article-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.article-badge {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  background: var(--sky-100);
  color: var(--sky-700);
  border: 1px solid var(--sky-200);
}

.article-date {
  font-size: 0.8rem;
  color: var(--text-light);
}

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

.article-card:hover .article-card-title {
  color: var(--sky-600);
}

.article-card-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 18px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 14px;
  border-top: 1px solid var(--sky-100);
  font-size: 0.85rem;
  color: var(--sky-600);
  font-weight: 600;
}

.article-card-footer svg {
  transition: transform var(--transition-fast);
}

.article-card:hover .article-card-footer svg {
  transform: translateX(4px);
}

/* 文章详情页专属排版 (Single Article Page) */
.article-page-wrap {
  max-width: 900px;
  margin: 40px auto 80px;
  padding: 0 20px;
}

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

.article-breadcrumb a {
  color: var(--sky-700);
  text-decoration: none;
}

.article-breadcrumb a:hover {
  text-decoration: underline;
}

.article-main-container {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow-sm);
}

.article-header {
  border-bottom: 1px solid var(--sky-100);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.article-main-title {
  font-size: 2.2rem;
  font-weight: 900;
  color: var(--deep-slate);
  line-height: 1.3;
  margin-bottom: 18px;
  letter-spacing: -0.02em;
}

.article-post-meta {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-light);
  flex-wrap: wrap;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.85;
  color: #334155;
}

.article-content h2 {
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--deep-slate);
  margin-top: 38px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--sky-100);
  display: flex;
  align-items: center;
  gap: 8px;
}

.article-content h2::before {
  content: "";
  display: inline-block;
  width: 5px;
  height: 20px;
  background: var(--sky-500);
  border-radius: 2px;
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--sky-900);
  margin-top: 26px;
  margin-bottom: 12px;
}

.article-content p {
  margin-bottom: 18px;
}

.article-content ul, .article-content ol {
  margin-left: 24px;
  margin-bottom: 22px;
}

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

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

.article-content a:hover {
  color: var(--sky-800);
}

.article-content blockquote {
  border-left: 4px solid var(--sky-400);
  padding: 16px 20px;
  background: var(--sky-50);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 24px 0;
  color: var(--text-muted);
  font-style: italic;
}

/* 文章内部高转化 CTA Banner */
.article-cta-box {
  background: linear-gradient(135deg, #0c4a6e 0%, #0369a1 50%, #0284c7 100%);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  color: #ffffff;
  text-align: center;
  margin: 40px 0;
  box-shadow: 0 12px 30px -4px rgba(2, 132, 199, 0.4);
}

.article-cta-box h3 {
  color: #ffffff;
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.article-cta-box p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.05rem;
  max-width: 620px;
  margin: 0 auto 24px;
}

.article-cta-box .btn-cta {
  background: #ffffff;
  color: var(--sky-800) !important;
  font-weight: 800;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.article-cta-box .btn-cta:hover {
  background: var(--sky-50);
  color: var(--sky-900) !important;
  transform: translateY(-2px);
}

/* ==========================================================================
   响应式断点适配 (@media)
   移动端优先，触控友好尺寸
   ========================================================================== */
@media (max-width: 992px) {
  .hero-split-grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .hero-text-col {
    text-align: center;
  }
  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }
  .hero-actions {
    justify-content: center;
  }
  .hero-meta {
    justify-content: center;
  }
  .hero-dynamic-card {
    max-width: 520px;
    margin: 0 auto;
  }
  .hero-title {
    font-size: 2.75rem;
  }
  .features-grid,
  .pricing-grid,
  .reviews-grid {
    grid-template-columns: 1fr;
    max-width: 580px;
    margin-left: auto;
    margin-right: auto;
  }
  .pricing-card.featured {
    transform: none;
  }
  .pricing-card.featured:hover {
    transform: translateY(-6px);
  }
  .media-ai-container {
    grid-template-columns: 1fr;
  }
  .apps-chip-grid {
    grid-template-columns: 1fr;
  }
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .site-header .header-inner {
    height: auto;
    padding-top: 10px;
    padding-bottom: 8px;
    flex-wrap: wrap;
  }
  .nav-links {
    display: flex;
    order: 3;
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding: 6px 0 2px;
    gap: 8px;
    scrollbar-width: none;
  }
  .nav-links::-webkit-scrollbar {
    display: none;
  }
  .nav-item {
    font-size: 0.82rem;
    padding: 4px 10px;
    background: var(--sky-50);
    border: 1px solid var(--sky-200);
    border-radius: var(--radius-full);
    flex-shrink: 0;
  }
  .hero-section {
    padding: 40px 0 35px;
  }
  .badge-float-1,
  .badge-float-2 {
    display: none; /* 避免超小屏幕溢出 */
  }
  .hero-meta {
    flex-direction: column;
    gap: 12px;
    align-items: center;
  }
  .section-nav-controller {
    right: 12px;
    padding: 6px 4px;
    gap: 8px;
  }
  .nav-arrow-btn {
    width: 38px;
    height: 38px;
  }
  .subpage-content {
    padding: 24px 18px;
    margin: 30px auto 50px;
  }
  .sitemap-grid {
    grid-template-columns: 1fr;
  }
  .footer-nav {
    flex-direction: column;
    gap: 16px;
  }
  .articles-grid {
    grid-template-columns: 1fr;
  }
  .article-main-container {
    padding: 24px 18px;
  }
  .article-main-title {
    font-size: 1.65rem;
  }
  .btn-cta {
    width: 100%;
    min-height: 48px; /* 适于手指点击 */
  }
}