/* ==========================================================================
   隐云机场 YINYUN AIRPORT - HIGH SPEED DEDICATED NETWORK DESIGN SYSTEM
   Color Palette: Slate Dark (#101317, #161A20, #1D222A), Light Slate (#E8ECEF)
   Tactical Accents: Cyan Glow (#00F0FF), Tactical Orange (#FF3B00), Node Green (#00FF9D)
   ========================================================================== */


:root {
  --bg-primary: #101317;
  --bg-secondary: #161a20;
  --bg-card: #1d222a;
  --bg-card-hover: #242a34;
  --ram-grey-light: #e8ecef;
  --ram-grey-muted: #9aa5b5;
  --ram-grey-dark: #3a424e;
  --border-grey: #2b323d;
  --border-active: #00f0ff;
  --accent-cyan: #00f0ff;
  --accent-cyan-glow: rgba(0, 240, 255, 0.25);
  --accent-orange: #ff3b00;
  --accent-green: #00ff9d;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --facet-clip: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 16px 100%, 0 calc(100% - 16px));
  --facet-clip-lg: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
  --facet-clip-btn: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Base Styles & Reset */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-primary);
  color: var(--ram-grey-light);
  font-family: var(--font-family);
  line-height: 1.6;
}

body {
  background-color: var(--bg-primary);
  background-image: 
    radial-gradient(circle at 50% 0%, rgba(0, 240, 255, 0.05) 0%, transparent 60%),
    linear-gradient(rgba(29, 34, 42, 0.3) 1px, transparent 1px),
    linear-gradient(90deg, rgba(29, 34, 42, 0.3) 1px, transparent 1px);
  background-size: 100% 100%, 40px 40px, 40px 40px;
  min-height: 100vh;
  overflow-x: hidden;
}

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

a:hover {
  color: #80f7ff;
  text-shadow: 0 0 8px var(--accent-cyan-glow);
}

/* Stealth Reticle Overlay Decorator */
.radar-grid-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 0;
  opacity: 0.15;
  background: 
    radial-gradient(circle at 50% 50%, transparent 0%, rgba(16, 19, 23, 0.8) 100%),
    repeating-linear-gradient(0deg, transparent, transparent 49px, rgba(0, 240, 255, 0.1) 50px);
}

/* Layout Elements */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* Header & Navigation */
header.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(16, 19, 23, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-grey);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--ram-grey-light);
  letter-spacing: 1px;
}

.logo-badge {
  width: 32px;
  height: 32px;
  background: var(--bg-card);
  border: 1px solid var(--accent-cyan);
  clip-path: polygon(0 0, 100% 0, 100% 70%, 70% 100%, 0 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 0.85rem;
  font-weight: 900;
}

nav.main-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

nav.main-nav a {
  color: var(--ram-grey-muted);
  font-size: 0.95rem;
  font-weight: 500;
  position: relative;
  padding: 6px 0;
}

nav.main-nav a:hover, nav.main-nav a.active {
  color: var(--ram-grey-light);
}

nav.main-nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--accent-cyan);
  transition: var(--transition);
}

nav.main-nav a:hover::after, nav.main-nav a.active::after {
  width: 100%;
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 20px;
  background: rgba(0, 240, 255, 0.08);
  border: 1px solid var(--accent-cyan);
  color: var(--accent-cyan) !important;
  font-weight: 700 !important;
  clip-path: var(--facet-clip-btn);
  transition: var(--transition);
}

.nav-cta:hover {
  background: var(--accent-cyan);
  color: #000 !important;
  box-shadow: 0 0 20px var(--accent-cyan-glow);
}

/* Mobile Toggle */
.mobile-menu-btn {
  display: none;
  background: none;
  border: 1px solid var(--border-grey);
  color: var(--ram-grey-light);
  font-size: 1.5rem;
  padding: 6px 12px;
  cursor: pointer;
}

/* Buttons */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 36px;
  background: linear-gradient(135deg, #00f0ff 0%, #0099ff 100%);
  color: #000;
  font-weight: 800;
  font-size: 1.05rem;
  clip-path: var(--facet-clip-btn);
  border: none;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 4px 20px rgba(0, 240, 255, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 240, 255, 0.5);
  color: #000;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 32px;
  background: var(--bg-card);
  border: 1px solid var(--border-grey);
  color: var(--ram-grey-light);
  font-weight: 600;
  font-size: 1rem;
  clip-path: var(--facet-clip-btn);
  cursor: pointer;
  transition: var(--transition);
}

.btn-secondary:hover {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  background: var(--bg-card-hover);
}

/* Stealth Cards */
.stealth-card {
  background: var(--bg-card);
  border: 1px solid var(--border-grey);
  clip-path: var(--facet-clip);
  padding: 32px;
  position: relative;
  transition: var(--transition);
}

.stealth-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 24px;
  background: var(--accent-cyan);
  opacity: 0.7;
}

.stealth-card:hover {
  border-color: var(--accent-cyan);
  background: var(--bg-card-hover);
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4), 0 0 15px rgba(0, 240, 255, 0.1);
}

/* Tactical Tags & Badges */
.tactical-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  background: rgba(0, 240, 255, 0.1);
  border: 1px solid rgba(0, 240, 255, 0.3);
  color: var(--accent-cyan);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 16px;
}

/* Hero Section */
.hero-section {
  padding: 80px 0 100px;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-content h1 {
  font-size: 2.8rem;
  font-weight: 900;
  line-height: 1.25;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

.hero-content h1 span.highlight {
  color: transparent;
  background: linear-gradient(90deg, #00f0ff, #e8ecef);
  -webkit-background-clip: text;
  background-clip: text;
}

.hero-content p.hero-desc {
  font-size: 1.15rem;
  color: var(--ram-grey-muted);
  margin-bottom: 32px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  padding-top: 24px;
  border-top: 1px solid var(--border-grey);
}

.metric-item .metric-val {
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--accent-cyan);
  font-family: monospace;
}

.metric-item .metric-label {
  font-size: 0.85rem;
  color: var(--ram-grey-muted);
}

.hero-visual {
  position: relative;
}

.radar-display-box {
  background: var(--bg-card);
  border: 1px solid var(--border-grey);
  clip-path: var(--facet-clip-lg);
  padding: 16px;
  position: relative;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
}

.radar-display-box img {
  width: 100%;
  height: auto;
  display: block;
  filter: contrast(1.1) brightness(0.95);
  border: 1px solid rgba(0, 240, 255, 0.2);
}

.radar-scan-line {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent-cyan), transparent);
  box-shadow: 0 0 15px var(--accent-cyan);
  animation: radarScan 4s linear infinite;
  pointer-events: none;
}

@keyframes radarScan {
  0% { top: 0%; opacity: 0.8; }
  50% { top: 100%; opacity: 0.8; }
  100% { top: 0%; opacity: 0.8; }
}

.rcs-status-tag {
  position: absolute;
  bottom: 24px;
  right: 24px;
  background: rgba(16, 19, 23, 0.9);
  border: 1px solid var(--accent-cyan);
  padding: 8px 16px;
  font-family: monospace;
  font-size: 0.8rem;
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  gap: 8px;
}

.rcs-status-tag .pulse-dot {
  width: 8px;
  height: 8px;
  background: var(--accent-green);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--accent-green);
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

/* Section Common */
.section {
  padding: 90px 0;
  border-bottom: 1px solid rgba(43, 50, 61, 0.5);
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 60px;
}

.section-header h2 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--ram-grey-light);
}

.section-header p {
  color: var(--ram-grey-muted);
  font-size: 1.05rem;
}

/* Grid Layouts */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

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

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
}

/* Advantage Card */
.advantage-card {
  height: 100%;
}

.advantage-icon {
  width: 54px;
  height: 54px;
  background: rgba(0, 240, 255, 0.08);
  border: 1px solid var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--accent-cyan);
  margin-bottom: 20px;
  clip-path: polygon(0 0, 100% 0, 100% 70%, 70% 100%, 0 100%);
}

.advantage-card h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
  color: var(--ram-grey-light);
}

.advantage-card p {
  color: var(--ram-grey-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* Pricing Card */
.pricing-card {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.pricing-card.featured {
  border-color: var(--accent-cyan);
  background: linear-gradient(180deg, rgba(0, 240, 255, 0.05) 0%, var(--bg-card) 100%);
}

.pricing-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  background: var(--accent-cyan);
  color: #000;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 4px 10px;
  clip-path: var(--facet-clip-btn);
}

.pricing-header h3 {
  font-size: 1.4rem;
  margin-bottom: 10px;
}

.pricing-price {
  font-size: 2.4rem;
  font-weight: 900;
  color: var(--accent-cyan);
  margin: 16px 0;
  font-family: monospace;
}

.pricing-price span {
  font-size: 0.9rem;
  color: var(--ram-grey-muted);
  font-weight: 400;
}

.pricing-features {
  list-style: none;
  margin: 24px 0 32px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.95rem;
  color: var(--ram-grey-muted);
}

.pricing-features li::before {
  content: '✓';
  color: var(--accent-cyan);
  font-weight: 900;
}

/* Target Audience */
.audience-card h3 {
  font-size: 1.25rem;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.audience-card p {
  color: var(--ram-grey-muted);
  font-size: 0.95rem;
}

/* Tutorial Section */
.tutorial-preview-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.tutorial-steps {
  margin: 16px 0 24px;
}

.step-item {
  display: flex;
  gap: 12px;
  margin-bottom: 12px;
}

.step-num {
  width: 24px;
  height: 24px;
  background: rgba(0, 240, 255, 0.1);
  border: 1px solid var(--accent-cyan);
  color: var(--accent-cyan);
  font-size: 0.8rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-text {
  font-size: 0.9rem;
  color: var(--ram-grey-muted);
}

/* Testimonials */
.review-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-text {
  font-size: 0.95rem;
  color: var(--ram-grey-muted);
  font-style: italic;
  margin-bottom: 20px;
  line-height: 1.7;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-avatar {
  width: 42px;
  height: 42px;
  background: var(--ram-grey-dark);
  border: 1px solid var(--accent-cyan);
  clip-path: polygon(0 0, 100% 0, 100% 70%, 70% 100%, 0 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: var(--accent-cyan);
}

.author-info h4 {
  font-size: 0.95rem;
  color: var(--ram-grey-light);
}

.author-info p {
  font-size: 0.8rem;
  color: var(--ram-grey-muted);
}

/* FAQ Component */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 900px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-grey);
  clip-path: var(--facet-clip-btn);
  overflow: hidden;
}

.faq-question {
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ram-grey-light);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
  transition: var(--transition);
}

.faq-question:hover {
  color: var(--accent-cyan);
}

.faq-icon {
  width: 24px;
  height: 24px;
  border: 1px solid var(--border-grey);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--accent-cyan);
  transition: transform 0.3s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
  background: rgba(16, 19, 23, 0.4);
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 0 24px 20px;
  border-top: 1px solid rgba(43, 50, 61, 0.4);
}

.faq-answer p {
  color: var(--ram-grey-muted);
  font-size: 0.95rem;
  line-height: 1.8;

  margin-top: 12px;
}

/* Article List Component */
.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.article-card-mini {
  background: var(--bg-card);
  border: 1px solid var(--border-grey);
  clip-path: var(--facet-clip-btn);
  padding: 24px;
  transition: var(--transition);
}

.article-card-mini:hover {
  border-color: var(--accent-cyan);
  background: var(--bg-card-hover);
}

.article-card-mini h3 {
  font-size: 1.15rem;
  margin-bottom: 10px;
  line-height: 1.5;
}

.article-card-mini p {
  font-size: 0.9rem;
  color: var(--ram-grey-muted);
  margin-bottom: 16px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: var(--ram-grey-muted);
}

/* Article Detail Page Layout */
.article-container {
  max-width: 860px;
  margin: 40px auto 80px;
  padding: 0 24px;
}

.breadcrumb {
  display: flex;
  gap: 8px;
  align-items: center;
  font-size: 0.85rem;
  color: var(--ram-grey-muted);
  margin-bottom: 24px;
}

.breadcrumb a {
  color: var(--ram-grey-muted);
}

.breadcrumb a:hover {
  color: var(--accent-cyan);
}

.article-header {
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-grey);
}

.article-header h1 {
  font-size: 2.2rem;
  font-weight: 900;
  line-height: 1.3;
  margin-bottom: 16px;
  color: var(--ram-grey-light);
}

.article-info {
  display: flex;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--ram-grey-muted);
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.9;
  color: #d8deee;
}

.article-content h2 {
  font-size: 1.6rem;
  margin: 40px 0 20px;
  color: var(--ram-grey-light);
  border-left: 3px solid var(--accent-cyan);
  padding-left: 14px;
}

.article-content h3 {
  font-size: 1.3rem;
  margin: 30px 0 16px;
  color: var(--ram-grey-light);
}

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

.article-content ul, .article-content ol {
  margin: 0 0 24px 24px;
  color: #c0c8d8;
}

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

.article-content blockquote {
  background: rgba(0, 240, 255, 0.05);
  border-left: 4px solid var(--accent-cyan);
  padding: 16px 24px;
  margin: 24px 0;
  font-style: italic;
  color: var(--ram-grey-light);
}

.article-cta-box {
  background: linear-gradient(135deg, rgba(0, 240, 255, 0.1) 0%, rgba(29, 34, 42, 0.8) 100%);
  border: 1px solid var(--accent-cyan);
  clip-path: var(--facet-clip);
  padding: 32px;
  text-align: center;
  margin: 40px 0;
}

.article-cta-box h3 {
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.article-cta-box p {
  color: var(--ram-grey-muted);
  margin-bottom: 20px;
}

/* Related Recommendations & Internal Links */
.related-posts {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 1px solid var(--border-grey);
}

.related-posts h3 {
  font-size: 1.4rem;
  margin-bottom: 24px;
}

/* Article FAQ Block */
.article-faq-section {
  margin-top: 50px;
  background: var(--bg-card);
  border: 1px solid var(--border-grey);
  clip-path: var(--facet-clip);
  padding: 32px;
}

.article-faq-section h3 {
  font-size: 1.4rem;
  margin-bottom: 24px;
  color: var(--accent-cyan);
}

/* Footer */
footer.site-footer {
  background: #0b0d10;
  border-top: 1px solid var(--border-grey);
  padding: 70px 0 30px;
  margin-top: 80px;
}

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

.footer-brand p {
  color: var(--ram-grey-muted);
  font-size: 0.9rem;
  margin-top: 16px;
  line-height: 1.7;
}

.footer-col h4 {
  font-size: 1.05rem;
  margin-bottom: 20px;
  color: var(--ram-grey-light);
  border-bottom: 2px solid var(--accent-cyan);
  display: inline-block;
  padding-bottom: 6px;
}

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

.footer-col a {
  color: var(--ram-grey-muted);
  font-size: 0.9rem;
}

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

.footer-bottom {
  padding-top: 30px;
  border-top: 1px solid rgba(43, 50, 61, 0.5);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--ram-grey-muted);
  flex-wrap: wrap;
  gap: 16px;
}

/* Responsive Styles */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .grid-3, .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  .article-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .hero-content h1 {
    font-size: 2rem;
  }
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  nav.main-nav {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    background: rgba(16, 19, 23, 0.98);
    flex-direction: column;
    padding: 24px;
    border-bottom: 1px solid var(--border-grey);
    gap: 16px;
  }
  nav.main-nav.show {
    display: flex;
  }
  .mobile-menu-btn {
    display: block;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}