/* TAG机场 (TAG Airport) - High-Impact Red & White Theme (红白色系) */
:root {
  --primary-red: #EF233C;
  --primary-dark-red: #D90429;
  --primary-hover-red: #FF4D5E;
  --red-glow: rgba(239, 35, 60, 0.35);
  --red-glow-strong: rgba(217, 4, 41, 0.6);
  --bg-dark: #A71D2A;
  --bg-card: rgba(255, 255, 255, 0.12);
  --bg-card-hover: rgba(255, 255, 255, 0.2);
  --text-main: #FFFFFF;
  --text-muted: #F8FAFC;
  --text-dim: #E2E8F0;
  --border-color: rgba(255, 255, 255, 0.25);
  --border-red: #FFFFFF;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  --shadow-main: 0 10px 30px rgba(0, 0, 0, 0.2);
  --shadow-red: 0 12px 32px rgba(255, 255, 255, 0.25);
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-family);
  background: linear-gradient(135deg, #D90429 0%, #900C1E 40%, #D90429 70%, #EF233C 100%);
  background-attachment: fixed;
  color: var(--text-main);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
}

/* Dynamic Canvas Background */
#bg-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
  opacity: 0.85;
}

.content-wrapper {
  position: relative;
  z-index: 1;
}

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

/* Announcement Top Bar */
.top-announcement {
  background: linear-gradient(90deg, #D90429, #E63946, #D90429);
  background-size: 200% 200%;
  animation: gradientShift 6s ease infinite;
  color: #FFFFFF;
  font-size: 14px;
  font-weight: 600;
  text-align: center;
  padding: 10px 16px;
  letter-spacing: 0.5px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.announcement-badge {
  background: rgba(255, 255, 255, 0.25);
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: 12px;
  text-transform: uppercase;
}

/* Sticky Header Navbar */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(167, 29, 42, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.logo-badge {
  width: 44px;
  height: 44px;
  background: #FFFFFF;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 18px;
  color: #D90429;
  box-shadow: 0 4px 15px rgba(255, 255, 255, 0.4);
  letter-spacing: 0.5px;
  font-style: italic;
}

.brand-name {
  font-size: 22px;
  font-weight: 800;
  color: #FFFFFF;
  letter-spacing: -0.5px;
}

.brand-name span {
  color: #FFE6E8;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  font-size: 15px;
  font-weight: 600;
  transition: all 0.2s ease;
}

.nav-links a:hover {
  color: #FFFFFF;
  text-shadow: 0 0 10px rgba(255, 255, 255, 0.6);
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Primary CTA Button */
.btn-primary {
  background: #FFFFFF;
  color: #D90429;
  font-size: 15px;
  font-weight: 800;
  padding: 12px 26px;
  border-radius: var(--radius-full);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: none;
  cursor: pointer;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px rgba(255, 255, 255, 0.4);
  background: #FFF0F2;
  color: #B70320;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.15);
  color: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.4);
  font-size: 15px;
  font-weight: 600;
  padding: 12px 26px;
  border-radius: var(--radius-full);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.3);
  border-color: #FFFFFF;
  color: #FFFFFF;
}

/* Hero Banner Section */
.hero-section {
  padding: 100px 0 80px;
  text-align: center;
  position: relative;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.4);
  color: #FFFFFF;
  padding: 6px 18px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 56px;
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -1.5px;
  margin-bottom: 24px;
  color: #FFFFFF;
}

.hero-title .highlight {
  color: #FFF0F2;
  text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
  font-size: 20px;
  color: var(--text-muted);
  max-width: 760px;
  margin: 0 auto 40px;
  font-weight: 400;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin-bottom: 48px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  max-width: 960px;
  margin: 0 auto;
  background: var(--bg-card);
  padding: 28px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-main);
}

.stat-item h4 {
  font-size: 32px;
  font-weight: 800;
  color: var(--primary-red);
}

.stat-item p {
  font-size: 14px;
  color: var(--text-muted);
}

/* Section Common Styling */
.section-padding {
  padding: 90px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 56px;
}

.section-title {
  font-size: 38px;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.section-subtitle {
  font-size: 17px;
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto;
}

/* Node Latency Monitor Section */
.node-monitor-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-main);
}

.monitor-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
}

.monitor-status-indicator {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 15px;
}

.pulse-dot {
  width: 10px;
  height: 10px;
  background-color: #22C55E;
  border-radius: 50%;
  box-shadow: 0 0 10px #22C55E;
  animation: pulseGreen 2s infinite;
}

.btn-ping-test {
  background: rgba(230, 57, 70, 0.15);
  color: var(--primary-red);
  border: 1px solid var(--border-red);
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-ping-test:hover {
  background: var(--primary-red);
  color: #FFFFFF;
}

.node-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.node-item {
  background: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  transition: all 0.2s ease;
}

.node-item:hover {
  background: #FFF0F2;
  transform: translateY(-2px);
}

.node-info {
  display: flex;
  align-items: center;
  gap: 14px;
}

.node-flag {
  font-size: 24px;
}

.node-name {
  font-weight: 700;
  font-size: 16px;
  color: #0F172A;
}

.node-desc {
  font-size: 13px;
  color: #475569;
}

.node-ping {
  font-weight: 800;
  font-size: 15px;
  color: #16A34A;
  background: rgba(22, 163, 74, 0.12);
  padding: 4px 10px;
  border-radius: 6px;
}

/* Pricing Section */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.pricing-card {
  background: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.6);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  position: relative;
  display: flex;
  flex-direction: column;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.12);
  transition: all 0.3s ease;
}

.pricing-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
}

.pricing-card.popular {
  border: 3px solid #D90429;
  background: #FFFFFF;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.25);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, #D90429, #EF233C);
  color: #FFFFFF;
  font-size: 12px;
  font-weight: 800;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  letter-spacing: 0.5px;
}

.pricing-header h3 {
  font-size: 22px;
  font-weight: 800;
  color: #0F172A;
  margin-bottom: 8px;
}

.pricing-header p {
  color: #64748B;
  font-size: 14px;
  margin-bottom: 24px;
}

.pricing-price {
  font-size: 40px;
  font-weight: 900;
  color: #D90429;
  margin-bottom: 24px;
}

.pricing-price span {
  font-size: 15px;
  font-weight: 400;
  color: #64748B;
}

.pricing-price span {
  font-size: 15px;
  font-weight: 400;
  color: var(--text-muted);
}

.pricing-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: #334155;
  margin-bottom: 12px;
}

.pricing-features li svg {
  color: #D90429;
  flex-shrink: 0;
}

.pricing-card .btn-primary {
  background: linear-gradient(135deg, #D90429, #EF233C);
  color: #FFFFFF;
  width: 100%;
  justify-content: center;
}

.pricing-card .btn-secondary {
  background: #FFF0F2;
  color: #D90429;
  border: 1px solid #D90429;
  width: 100%;
  justify-content: center;
}

.pricing-card .btn-secondary:hover {
  background: #D90429;
  color: #FFFFFF;
}

/* Core Advantages */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.advantage-card {
  background: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
}

.advantage-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.18);
  background: #FFF0F2;
}

.advantage-icon {
  width: 56px;
  height: 56px;
  background: rgba(217, 4, 41, 0.1);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #D90429;
  margin-bottom: 20px;
}

.advantage-card h3 {
  font-size: 20px;
  font-weight: 700;
  color: #0F172A;
  margin-bottom: 12px;
}

.advantage-card p {
  font-size: 14px;
  color: #475569;
  line-height: 1.6;
}

/* FAQ Section */
.faq-container {
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  background: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow: hidden;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  transition: all 0.2s ease;
}

.faq-question {
  padding: 22px 28px;
  font-size: 17px;
  font-weight: 700;
  color: #0F172A;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  user-select: none;
}

.faq-question:hover {
  color: #D90429;
}

.faq-icon {
  transition: transform 0.3s ease;
  color: #D90429;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  background: #FFF0F2;
}

.faq-answer-content {
  padding: 0 28px 24px;
  color: #334155;
  font-size: 15px;
  line-height: 1.7;
}

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

/* Articles Knowledge Base Section */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.article-card {
  background: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  text-decoration: none;
  color: inherit;
}

.article-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.18);
  background: #FFF0F2;
}

.article-tag {
  align-self: flex-start;
  background: rgba(217, 4, 41, 0.1);
  color: #D90429;
  font-size: 12px;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  margin-bottom: 16px;
}

.article-card h3 {
  font-size: 19px;
  font-weight: 700;
  color: #0F172A;
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card p {
  font-size: 14px;
  color: #475569;
  margin-bottom: 20px;
  flex-grow: 1;
  line-height: 1.6;
}

.article-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: #64748B;
  border-top: 1px solid #E2E8F0;
  padding-top: 16px;
}

.read-more {
  color: #D90429;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 4px;
}

/* User Testimonials Section */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.testimonial-card {
  background: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-lg);
  padding: 28px;
  position: relative;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.rating-stars {
  color: #FFB800;
  margin-bottom: 16px;
  font-size: 16px;
}

.testimonial-quote {
  font-size: 15px;
  color: #334155;
  margin-bottom: 24px;
  line-height: 1.6;
  font-style: italic;
}

.user-profile {
  display: flex;
  align-items: center;
  gap: 12px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, #D90429, #EF233C);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #FFFFFF;
}

.user-info h4 {
  font-size: 15px;
  font-weight: 700;
  color: #0F172A;
}

.user-info p {
  font-size: 12px;
  color: #64748B;
}

/* Footer */
.site-footer {
  background: #7A0813;
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding: 60px 0 30px;
  color: #FFFFFF;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  margin-bottom: 40px;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 14px;
  margin-top: 12px;
  max-width: 320px;
}

.footer-links h4 {
  font-size: 16px;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 16px;
}

.footer-links ul {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: #FFFFFF;
  text-decoration: underline;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding-top: 24px;
  text-align: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: 13px;
}

/* Keyframe Animations */
@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

@keyframes pulseGreen {
  0% { box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.4); }
  70% { box-shadow: 0 0 0 10px rgba(34, 197, 94, 0); }
  100% { box-shadow: 0 0 0 0 rgba(34, 197, 94, 0); }
}

/* Responsive Layout */
@media (max-width: 1024px) {
  .pricing-grid, .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-grid, .testimonials-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .hero-title {
    font-size: 36px;
  }
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid, .advantages-grid, .articles-grid, .testimonials-grid {
    grid-template-columns: 1fr;
  }
}