/* ==========================================================================
   扬帆机场官网 - 视觉与设计系统 (Yangfan Edge Network - High-End SaaS Dark Theme)
   设计风格：Linear / Vercel 极客科技风 · 微噪点深色渐变 · 细边框毛玻璃 · SVG 动态数据流
   ========================================================================== */

:root {
  --bg-deep: #08090d;
  --bg-subtle: #0d0f17;
  --bg-card: rgba(18, 22, 34, 0.65);
  --bg-card-hover: rgba(26, 32, 50, 0.85);
  --bg-glass: rgba(13, 16, 26, 0.75);
  --bg-glass-heavy: rgba(10, 12, 20, 0.92);

  --primary: #06b6d4;         /* Cyber Cyan */
  --primary-hover: #22d3ee;
  --primary-glow: rgba(6, 182, 212, 0.25);
  --indigo: #6366f1;          /* Linear Indigo */
  --indigo-glow: rgba(99, 102, 241, 0.3);
  --accent: #10b981;          /* Emerald Green */
  --accent-glow: rgba(16, 185, 129, 0.25);

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --text-light: #475569;

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-light: rgba(255, 255, 255, 0.14);
  --border-hover: rgba(99, 102, 241, 0.4);
  --border-cyan: rgba(6, 182, 212, 0.4);

  --gradient-brand: linear-gradient(135deg, #6366f1 0%, #06b6d4 100%);
  --gradient-accent: linear-gradient(135deg, #10b981 0%, #06b6d4 100%);
  --gradient-text: linear-gradient(180deg, #ffffff 0%, #cbd5e1 100%);
  --gradient-glow: radial-gradient(circle at 50% 50%, rgba(99, 102, 241, 0.18) 0%, rgba(6, 182, 212, 0.08) 45%, transparent 75%);

  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-card: 0 8px 32px -8px rgba(0, 0, 0, 0.6), inset 0 1px 0 rgba(255, 255, 255, 0.08);
  --shadow-glow: 0 0 30px rgba(99, 102, 241, 0.25);

  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --transition: all 0.28s cubic-bezier(0.16, 1, 0.3, 1);
}

/* ==========================================================================
   Base & Resets
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-deep);
  color-scheme: dark;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-deep);
  color: var(--text-main);
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Noise overlay */
body::before {
  content: "";
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background-image: radial-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 0);
  background-size: 24px 24px;
  pointer-events: none;
  z-index: -1;
  opacity: 0.6;
}

/* Dynamic Particle / Mesh Canvas */
#bg-canvas {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  z-index: -2;
  pointer-events: none;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  outline: none;
}

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   Typography & Reusable Utilities
   ========================================================================== */
.gradient-text {
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

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

.section-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(99, 102, 241, 0.12);
  border: 1px solid rgba(99, 102, 241, 0.3);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: #a5b4fc;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 56px;
}

.section-title {
  font-size: 2.4rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.25;
  margin-bottom: 16px;
  color: #fff;
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.92rem;
  padding: 10px 22px;
  border-radius: var(--radius-full);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  user-select: none;
}

.btn-primary {
  background: var(--gradient-brand);
  color: #ffffff;
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 28px rgba(6, 182, 212, 0.55), inset 0 1px 0 rgba(255, 255, 255, 0.35);
}

.btn-accent {
  background: var(--gradient-accent);
  color: #ffffff;
  box-shadow: 0 0 20px rgba(16, 185, 129, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 28px rgba(16, 185, 129, 0.55);
}

.btn-outline {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-main);
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(10px);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.09);
  border-color: rgba(255, 255, 255, 0.25);
  transform: translateY(-1px);
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1rem;
}

/* Glass Card */
.glass-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(20px);
  transition: var(--transition);
}

.glass-card:hover {
  border-color: var(--border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-3px);
  box-shadow: 0 12px 40px -10px rgba(0, 0, 0, 0.7), 0 0 20px rgba(99, 102, 241, 0.15);
}

/* ==========================================================================
   Top Announcement Bar (广告语与特色)
   ========================================================================== */
.top-marquee {
  background: linear-gradient(90deg, rgba(13, 16, 26, 0.95), rgba(30, 27, 75, 0.9), rgba(13, 16, 26, 0.95));
  border-bottom: 1px solid rgba(99, 102, 241, 0.25);
  font-size: 0.85rem;
  padding: 8px 0;
  position: relative;
  z-index: 100;
}

.top-marquee-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.top-marquee-left {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #e2e8f0;
}

.marquee-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(99, 102, 241, 0.2);
  border: 1px solid rgba(99, 102, 241, 0.4);
  color: #818cf8;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.marquee-badge::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 8px #10b981;
  animation: pulse-dot 1.8s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.75); }
}

.marquee-right {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.82rem;
  color: var(--text-muted);
}

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

.marquee-link:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

/* ==========================================================================
   Header Navbar
   ========================================================================== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 99;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #fff;
}

.logo-symbol {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--gradient-brand);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 16px rgba(99, 102, 241, 0.4);
  font-size: 1.15rem;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-size: 1.15rem;
  font-weight: 800;
  line-height: 1.1;
  color: #ffffff;
}

.logo-sub {
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--primary);
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 6px;
}

.nav-links a {
  padding: 8px 14px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-muted);
}

.nav-links a:hover, .nav-links a.active {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.06);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* ==========================================================================
   Hero Section (高客单极简风 SaaS / Tech 极简路线)
   ========================================================================== */
.hero {
  position: relative;
  padding: 90px 0 80px;
  text-align: center;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 480px;
  background: radial-gradient(ellipse at center, rgba(99, 102, 241, 0.16) 0%, rgba(6, 182, 212, 0.08) 40%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero .container {
  position: relative;
  z-index: 1;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: #e2e8f0;
  margin-bottom: 28px;
  backdrop-filter: blur(12px);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-tag-icon {
  color: var(--primary);
  font-size: 0.95rem;
}

.hero-title {
  font-size: 3.4rem;
  font-weight: 850;
  line-height: 1.18;
  letter-spacing: -0.035em;
  margin-bottom: 24px;
  max-width: 980px;
  margin-left: auto;
  margin-right: auto;
}

.hero-sub {
  font-size: 1.2rem;
  line-height: 1.7;
  color: var(--text-muted);
  max-width: 780px;
  margin: 0 auto 36px;
  font-weight: 400;
}

.hero-sub strong {
  color: #f1f5f9;
  font-weight: 600;
}

/* 动态徽标 (Dynamic Badges) */
.hero-badges-row {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 40px;
}

.dynamic-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: rgba(18, 22, 34, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 600;
  color: #f8fafc;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
  transition: var(--transition);
}

.dynamic-badge:hover {
  border-color: var(--primary);
  background: rgba(22, 28, 44, 0.9);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(6, 182, 212, 0.2);
}

.dynamic-badge .badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 10px var(--primary);
}

.dynamic-badge:nth-child(2) .badge-dot {
  background: #a855f7;
  box-shadow: 0 0 10px #a855f7;
}

.dynamic-badge:nth-child(3) .badge-dot {
  background: var(--accent);
  box-shadow: 0 0 10px var(--accent);
}

/* CTA Group */
.hero-ctas {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 60px;
  flex-wrap: wrap;
}

/* Hero Network Stats Matrix */
.hero-matrix {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 1040px;
  margin: 0 auto;
}

.matrix-card {
  background: rgba(15, 19, 30, 0.6);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px 18px;
  text-align: left;
  backdrop-filter: blur(16px);
  transition: var(--transition);
}

.matrix-card:hover {
  border-color: rgba(99, 102, 241, 0.35);
  background: rgba(20, 26, 42, 0.8);
  transform: translateY(-2px);
}

.matrix-val {
  font-size: 1.7rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #fff;
  margin-bottom: 4px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.matrix-unit {
  font-size: 0.85rem;
  color: var(--primary);
  font-weight: 600;
}

.matrix-label {
  font-size: 0.84rem;
  color: var(--text-muted);
  line-height: 1.4;
}

/* ==========================================================================
   Section 3: 三线测速 / 延迟仪表盘与实时状态板块 (Live Dashboard)
   ========================================================================== */
.status-section {
  padding: 80px 0;
  position: relative;
}

.status-dashboard-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(24px);
  margin-bottom: 40px;
}

.dashboard-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 30px;
}

.dashboard-title-group h3 {
  font-size: 1.45rem;
  font-weight: 750;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 10px;
}

.live-indicator {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent);
  background: rgba(16, 185, 129, 0.12);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.live-indicator::before {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse-dot 1.5s infinite;
}

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

.dashboard-meta span strong {
  color: #fff;
}

/* 4 Core Regional Gauges */
.rtt-gauges-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 30px;
}

.rtt-gauge-card {
  background: rgba(13, 17, 28, 0.7);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  position: relative;
  overflow: hidden;
  transition: var(--transition);
}

.rtt-gauge-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

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

.gauge-region {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1rem;
  color: #fff;
}

.gauge-flag {
  font-size: 1.3rem;
}

.gauge-tag {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--primary);
  background: rgba(6, 182, 212, 0.12);
  padding: 2px 8px;
  border-radius: var(--radius-full);
}

.gauge-rtt-wrap {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin-bottom: 8px;
}

.gauge-rtt-num {
  font-size: 2.2rem;
  font-weight: 850;
  color: var(--accent);
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
}

.gauge-rtt-unit {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
}

.gauge-bar-bg {
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 12px;
}

.gauge-bar-fill {
  height: 100%;
  background: var(--gradient-accent);
  border-radius: var(--radius-full);
  transition: width 0.6s ease;
}

.gauge-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.78rem;
  color: var(--text-dim);
}

/* Secondary Node Status Grid */
.nodes-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.node-card {
  background: rgba(13, 17, 28, 0.5);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: var(--transition);
}

.node-card:hover {
  border-color: rgba(255, 255, 255, 0.2);
  background: rgba(20, 26, 42, 0.75);
}

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

.node-flag {
  font-size: 1.25rem;
}

.node-name {
  font-size: 0.88rem;
  font-weight: 600;
  color: #f1f5f9;
}

.node-type {
  font-size: 0.72rem;
  color: var(--text-dim);
}

.node-ping-badge {
  text-align: right;
}

.ping-val {
  font-size: 0.92rem;
  font-weight: 750;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.status-dot-wrap {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 0.72rem;
  color: var(--text-muted);
}

.dot-green {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 6px var(--accent);
}

/* ==========================================================================
   Section 4: 套餐价格板块 (Pricing Section)
   ========================================================================== */
.pricing-section {
  padding: 90px 0;
  position: relative;
}

.pricing-billing-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(15, 19, 30, 0.9);
  padding: 5px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
  margin-top: 24px;
}

.billing-btn {
  padding: 8px 24px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
  background: transparent;
  transition: var(--transition);
}

.billing-btn.active {
  background: var(--gradient-brand);
  color: #fff;
  box-shadow: 0 0 16px rgba(99, 102, 241, 0.35);
}

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

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
  backdrop-filter: blur(20px);
}

.pricing-card:hover {
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-4px);
}

.pricing-card.popular {
  border-color: rgba(99, 102, 241, 0.5);
  background: linear-gradient(180deg, rgba(26, 32, 54, 0.8) 0%, rgba(14, 18, 30, 0.95) 100%);
  box-shadow: 0 12px 40px -10px rgba(99, 102, 241, 0.25), inset 0 1px 0 rgba(255, 255, 255, 0.15);
  transform: scale(1.03);
}

.pricing-card.popular:hover {
  transform: scale(1.03) translateY(-4px);
  border-color: var(--primary);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-brand);
  color: #fff;
  padding: 4px 16px;
  border-radius: var(--radius-full);
  font-size: 0.76rem;
  font-weight: 750;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  box-shadow: 0 4px 16px rgba(99, 102, 241, 0.5);
}

.card-plan-name {
  font-size: 1.35rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 8px;
}

.card-plan-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
  min-height: 42px;
  margin-bottom: 24px;
}

.card-price-wrap {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 8px;
}

.currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: #fff;
}

.big-price {
  font-size: 3.2rem;
  font-weight: 850;
  letter-spacing: -0.04em;
  color: #fff;
  line-height: 1;
}

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

.original-price {
  font-size: 0.95rem;
  color: var(--text-dim);
  text-decoration: line-through;
  margin-left: 8px;
}

.bonus-tag {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.25);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  margin-bottom: 28px;
  align-self: flex-start;
}

.plan-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 36px;
  flex-grow: 1;
}

.plan-features li {
  font-size: 0.9rem;
  color: #cbd5e1;
  display: flex;
  align-items: flex-start;
  gap: 10px;
  line-height: 1.5;
}

.plan-features li i {
  font-style: normal;
  color: var(--accent);
  font-weight: 800;
  font-size: 1rem;
  line-height: 1.2;
}

/* ==========================================================================
   Section 4 (Continued): 核心优势板块与拓扑示意图 (Advantages & Topology)
   ========================================================================== */
.advantages-section {
  padding: 90px 0;
  position: relative;
}

/* BGP 专线/IEPL 拓扑示意图 */
.topology-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(24px);
  margin-bottom: 50px;
  position: relative;
  overflow: hidden;
}

.topology-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 32px;
}

.topology-header h3 {
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
}

.audit-promise-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: #34d399;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 700;
}

.topology-diagram-flow {
  display: grid;
  grid-template-columns: 1fr auto 1.4fr auto 1fr auto 1.2fr;
  align-items: center;
  gap: 12px;
  padding: 24px 0;
}

.topo-node {
  background: rgba(15, 20, 32, 0.8);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px 16px;
  text-align: center;
  position: relative;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.topo-node.highlight-tunnel {
  border-color: var(--primary);
  background: linear-gradient(180deg, rgba(6, 182, 212, 0.12) 0%, rgba(99, 102, 241, 0.12) 100%);
  box-shadow: 0 0 24px rgba(6, 182, 212, 0.2);
}

.topo-icon {
  font-size: 1.8rem;
  margin-bottom: 8px;
}

.topo-title {
  font-size: 0.95rem;
  font-weight: 750;
  color: #fff;
  margin-bottom: 4px;
}

.topo-desc {
  font-size: 0.76rem;
  color: var(--text-muted);
  line-height: 1.35;
}

.topo-arrow {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  color: var(--primary);
}

.topo-arrow-line {
  width: 48px;
  height: 2px;
  background: linear-gradient(90deg, var(--indigo), var(--primary));
  position: relative;
}

.topo-arrow-line::after {
  content: "";
  position: absolute;
  top: -3px;
  right: 0;
  width: 8px;
  height: 8px;
  border-top: 2px solid var(--primary);
  border-right: 2px solid var(--primary);
  transform: rotate(45deg);
}

.topo-arrow-tag {
  font-size: 0.68rem;
  font-weight: 700;
  color: #a5b4fc;
}

.topology-footer-notes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid var(--border-subtle);
}

.topo-note-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.topo-note-icon {
  font-size: 1.25rem;
  line-height: 1;
}

.topo-note-text h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: #f1f5f9;
  margin-bottom: 4px;
}

.topo-note-text p {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.45;
}

/* 协议与客户端矩阵 (Protocol & Client Matrix) */
.client-matrix-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(24px);
  margin-bottom: 50px;
}

.client-matrix-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 32px;
}

.client-matrix-header h3 {
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 8px;
}

.client-matrix-header p {
  font-size: 0.92rem;
  color: var(--text-muted);
}

.client-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}

.client-card {
  background: rgba(13, 17, 28, 0.7);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 16px;
  text-align: center;
  transition: var(--transition);
}

.client-card:hover {
  border-color: var(--border-hover);
  background: rgba(22, 28, 46, 0.85);
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
}

.client-logo {
  width: 52px;
  height: 52px;
  margin: 0 auto 14px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
}

.client-name {
  font-size: 1rem;
  font-weight: 750;
  color: #fff;
  margin-bottom: 4px;
}

.client-os {
  font-size: 0.75rem;
  color: var(--primary);
  margin-bottom: 10px;
  font-weight: 600;
}

.client-badge {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 600;
  padding: 3px 8px;
  background: rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-full);
  color: #cbd5e1;
}

/* 核心优势网格 */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.adv-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  transition: var(--transition);
  backdrop-filter: blur(20px);
}

.adv-card:hover {
  border-color: var(--border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-3px);
}

.adv-icon-wrap {
  width: 54px;
  height: 54px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.15), rgba(6, 182, 212, 0.15));
  border: 1px solid rgba(99, 102, 241, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.adv-card h3 {
  font-size: 1.25rem;
  font-weight: 750;
  color: #fff;
  margin-bottom: 10px;
}

.adv-card p {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* ==========================================================================
   Section 5: 常见问题板块 (FAQ Section)
   ========================================================================= */
.faq-section {
  padding: 80px 0;
  position: relative;
}

.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
  backdrop-filter: blur(16px);
}

.faq-item:hover {
  border-color: rgba(255, 255, 255, 0.18);
}

.faq-item.active {
  border-color: var(--border-hover);
  background: rgba(22, 28, 44, 0.85);
}

.faq-question {
  padding: 22px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 700;
  color: #fff;
  user-select: none;
}

.faq-icon {
  font-size: 0.85rem;
  color: var(--primary);
  transition: transform 0.28s ease;
}

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

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
  padding: 0 28px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.active .faq-answer {
  max-height: 400px;
  padding-bottom: 24px;
}

/* ==========================================================================
   Section 5 (Continued): 知识库与教程板块 (Knowledge Base Section)
   ========================================================================== */
.kb-section {
  padding: 90px 0;
  position: relative;
}

.kb-tabs-row {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 36px;
}

.kb-tab {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.kb-tab:hover, .kb-tab.active {
  color: #fff;
  background: rgba(99, 102, 241, 0.2);
  border-color: rgba(99, 102, 241, 0.4);
}

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

.kb-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  backdrop-filter: blur(20px);
  transition: var(--transition);
  cursor: pointer;
}

.kb-card:hover {
  border-color: var(--border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-3px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.5);
}

.kb-tag {
  display: inline-block;
  font-size: 0.74rem;
  font-weight: 700;
  color: var(--primary);
  background: rgba(6, 182, 212, 0.12);
  padding: 2px 10px;
  border-radius: var(--radius-full);
  margin-bottom: 12px;
}

.kb-card h3 {
  font-size: 1.15rem;
  font-weight: 750;
  color: #fff;
  line-height: 1.45;
  margin-bottom: 10px;
}

.kb-excerpt {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.kb-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.78rem;
  color: var(--text-dim);
}

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

.read-more-link:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

/* ==========================================================================
   Section 6: 用户评价板块 (Testimonials Section)
   ========================================================================== */
.reviews-section {
  padding: 90px 0;
  position: relative;
}

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

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  backdrop-filter: blur(20px);
  transition: var(--transition);
}

.review-card:hover {
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-3px);
}

.review-stars {
  color: #fbbf24;
  font-size: 1.05rem;
  letter-spacing: 2px;
  margin-bottom: 16px;
}

.review-text {
  font-size: 0.95rem;
  color: #e2e8f0;
  line-height: 1.7;
  margin-bottom: 24px;
  font-style: normal;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 14px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--indigo), var(--primary));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1rem;
  color: #fff;
  box-shadow: 0 0 12px rgba(99, 102, 241, 0.35);
}

.user-meta h4 {
  font-size: 0.95rem;
  font-weight: 750;
  color: #fff;
  margin-bottom: 2px;
}

.user-meta span {
  font-size: 0.78rem;
  color: var(--text-dim);
}

/* ==========================================================================
   Article Detail Page Layout (for article-1.html to article-10.html)
   ========================================================================== */
.article-container {
  padding: 40px 20px 80px;
  max-width: 920px;
  margin: 0 auto;
}

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

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

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

.article-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 48px;
  backdrop-filter: blur(24px);
  box-shadow: var(--shadow-card);
}

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

.article-header h1 {
  font-size: 2.3rem;
  font-weight: 850;
  color: #fff;
  line-height: 1.3;
  margin: 14px 0;
  letter-spacing: -0.02em;
}

.article-meta-info {
  font-size: 0.86rem;
  color: var(--text-dim);
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.85;
  color: #e2e8f0;
}

.article-content h2 {
  font-size: 1.6rem;
  font-weight: 800;
  color: #fff;
  margin: 40px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-subtle);
}

.article-content h3 {
  font-size: 1.25rem;
  font-weight: 750;
  color: #f1f5f9;
  margin: 28px 0 12px;
}

.article-content p {
  margin-bottom: 18px;
  color: #cbd5e1;
}

.article-content strong {
  color: #fff;
  font-weight: 700;
}

.article-content ul, .article-content ol {
  margin: 16px 0 24px 24px;
  color: #cbd5e1;
}

.article-content li {
  margin-bottom: 10px;
  line-height: 1.7;
}

.article-content code {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  padding: 2px 8px;
  border-radius: var(--radius-xs);
  font-family: Consolas, Monaco, monospace;
  font-size: 0.9em;
  color: #a5b4fc;
}

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 28px 0;
  font-size: 0.94rem;
}

.article-content table tr, .article-box table tr {
  background: rgba(255, 255, 255, 0.03) !important;
}

.article-content th, .article-box table th {
  background: rgba(255, 255, 255, 0.08) !important;
  color: #fff !important;
  border: 1px solid var(--border-subtle) !important;
}

.article-content td, .article-box table td {
  border: 1px solid var(--border-subtle) !important;
  color: #cbd5e1 !important;
}

.modal-cta-box {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.15) 0%, rgba(6, 182, 212, 0.15) 100%);
  border: 1px solid rgba(99, 102, 241, 0.35);
  border-radius: var(--radius-md);
  padding: 32px;
  text-align: center;
  margin: 36px 0;
}

.modal-cta-box h3 {
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 8px;
}

.modal-cta-box p {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

/* ==========================================================================
   Article Modal Reader
   ========================================================================== */
.article-modal {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(12px);
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.article-modal.active {
  display: flex;
}

.modal-content-box {
  background: #0d101b;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 900px;
  max-height: 88vh;
  overflow-y: auto;
  padding: 40px;
  position: relative;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.8);
}

.modal-close-btn {
  position: absolute;
  top: 20px; right: 24px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #fff;
  width: 36px; height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  cursor: pointer;
  transition: var(--transition);
}

.modal-close-btn:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* ==========================================================================
   Footer Section
   ========================================================================== */
.footer {
  background: #050608;
  border-top: 1px solid var(--border-subtle);
  padding: 80px 0 40px;
  position: relative;
  z-index: 10;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr 1fr;
  gap: 48px;
  margin-bottom: 60px;
}

.footer-col h4 {
  font-size: 0.95rem;
  font-weight: 750;
  color: #fff;
  letter-spacing: 0.04em;
  margin-bottom: 20px;
}

.footer-col p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.65;
}

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

.footer-links a {
  font-size: 0.88rem;
  color: var(--text-dim);
}

.footer-links a:hover {
  color: #fff;
}

.footer-bottom {
  padding-top: 30px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.82rem;
  color: var(--text-dim);
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-matrix {
    grid-template-columns: repeat(2, 1fr);
  }
  .rtt-gauges-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .nodes-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 520px;
    margin: 0 auto;
  }
  .pricing-card.popular {
    transform: none;
  }
  .pricing-card.popular:hover {
    transform: translateY(-4px);
  }
  .topology-diagram-flow {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .topo-arrow {
    transform: rotate(90deg);
    margin: 6px 0;
  }
  .topology-footer-notes {
    grid-template-columns: 1fr;
  }
  .client-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .advantages-grid {
    grid-template-columns: 1fr;
  }
  .kb-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .reviews-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.3rem;
  }
  .hero-sub {
    font-size: 1rem;
  }
  .nav-links {
    display: none;
  }
  .hero-matrix {
    grid-template-columns: 1fr;
  }
  .rtt-gauges-grid {
    grid-template-columns: 1fr;
  }
  .nodes-grid {
    grid-template-columns: 1fr;
  }
  .client-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .kb-grid {
    grid-template-columns: 1fr;
  }
  .article-box {
    padding: 24px;
  }
  .article-header h1 {
    font-size: 1.6rem;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}