/* ==========================================================================
   69云机场 (69yun.cyou) - 官方落地页主样式表
   ========================================================================== */

:root {
  --bg-dark: #0b0f19;
  --bg-card: #131b2e;
  --bg-card-hover: #1c2742;
  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(56, 189, 248, 0.3);
  
  --primary-sky: #38bdf8;
  --primary-indigo: #818cf8;
  --primary-purple: #c084fc;
  --accent-cyan: #06b6d4;
  --accent-green: #10b981;

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-sub: #cbd5e1;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --radius-lg: 16px;
  --radius-md: 12px;
  --radius-sm: 8px;
  --transition-fast: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
  background: radial-gradient(circle at 50% 0%, rgba(56, 189, 248, 0.08) 0%, rgba(11, 15, 25, 1) 70%);
  min-height: 100vh;
}

a {
  color: var(--primary-sky);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: #7dd3fc;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.section-padding {
  padding: 80px 0;
}

.text-gradient {
  background: linear-gradient(135deg, var(--primary-sky), var(--primary-indigo), var(--primary-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Header & Navigation */
.header-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 15, 25, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  height: 72px;
  display: flex;
  align-items: center;
}

.nav-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 12px;
  color: #fff;
  font-weight: 700;
  font-size: 1.25rem;
}

.logo-img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
}

.logo-badge {
  font-size: 0.75rem;
  background: rgba(56, 189, 248, 0.15);
  color: var(--primary-sky);
  padding: 2px 8px;
  border-radius: 20px;
  border: 1px solid rgba(56, 189, 248, 0.3);
  font-weight: 600;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 28px;
}

.nav-links a {
  color: var(--text-sub);
  font-size: 0.95rem;
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--primary-sky);
}

/* Buttons */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: linear-gradient(135deg, #0284c7 0%, #4f46e5 100%);
  color: #ffffff !important;
  font-weight: 600;
  padding: 10px 22px;
  border-radius: 30px;
  box-shadow: 0 4px 18px rgba(2, 132, 199, 0.35);
  transition: all var(--transition-fast);
  border: none;
  cursor: pointer;
  text-align: center;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(2, 132, 199, 0.5);
  filter: brightness(1.1);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main) !important;
  border: 1px solid var(--border-color);
  font-weight: 600;
  padding: 10px 22px;
  border-radius: 30px;
  transition: all var(--transition-fast);
  cursor: pointer;
  text-align: center;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

/* Mobile Drawer Menu */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.5rem;
  cursor: pointer;
}

.mobile-nav-drawer {
  display: none;
  position: fixed;
  top: 72px;
  left: 0;
  width: 100%;
  background: rgba(19, 27, 46, 0.98);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  padding: 20px;
  z-index: 99;
}

.mobile-nav-drawer.active {
  display: block;
}

.mobile-nav-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav-links a {
  color: var(--text-main);
  font-size: 1.05rem;
  display: block;
  padding: 8px 0;
}

/* Section Header Structure */
.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 50px auto;
}

.section-tag {
  display: inline-block;
  font-size: 0.825rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--primary-sky);
  background: rgba(56, 189, 248, 0.1);
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 12px;
  border: 1px solid rgba(56, 189, 248, 0.2);
  font-weight: 600;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 16px;
}

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

/* Hero Section */
.hero-section {
  padding: 90px 0 60px 0;
  text-align: center;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(129, 140, 248, 0.12);
  border: 1px solid rgba(129, 140, 248, 0.3);
  color: var(--primary-indigo);
  padding: 6px 18px;
  border-radius: 30px;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.25rem;
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 20px;
  letter-spacing: -1px;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-sub);
  max-width: 820px;
  margin: 0 auto 36px auto;
  line-height: 1.8;
}

.hero-subtitle strong {
  color: var(--primary-sky);
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 50px;
  flex-wrap: wrap;
}

/* Counter Metrics Row */
.metrics-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 40px;
}

.metric-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 24px 16px;
  border-radius: var(--radius-md);
  text-align: center;
  transition: transform var(--transition-fast);
}

.metric-box:hover {
  transform: translateY(-4px);
  border-color: var(--border-glow);
}

.metric-num {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary-sky);
  margin-bottom: 6px;
}

.metric-label {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Latency Ping Monitor */
.ping-card-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

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

.ping-item {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

.ping-flag {
  font-size: 1.8rem;
}

.ping-name {
  font-weight: 700;
  font-size: 0.98rem;
  color: var(--text-main);
}

.ping-detail {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.ping-badge {
  text-align: right;
  min-width: 100px;
}

.ping-val {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--accent-green);
  display: inline-block;
  margin-bottom: 4px;
}

.ping-bar-bg {
  width: 100px;
  height: 6px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 3px;
  overflow: hidden;
}

.ping-bar-fill {
  height: 100%;
  background: var(--accent-green);
  border-radius: 3px;
  transition: width 0.5s ease;
}

/* Bento Grid Features */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.bento-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all var(--transition-fast);
}

.bento-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-glow);
  box-shadow: 0 12px 30px rgba(56, 189, 248, 0.1);
}

.bento-card.span-2 {
  grid-column: span 2;
}

.bento-icon {
  font-size: 2.2rem;
  margin-bottom: 18px;
}

.bento-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: #fff;
}

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

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

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: all var(--transition-fast);
}

.pricing-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-glow);
}

.pricing-card.popular {
  background: linear-gradient(180deg, rgba(30, 41, 71, 0.9) 0%, rgba(19, 27, 46, 1) 100%);
  border: 2px solid var(--primary-sky);
  box-shadow: 0 10px 40px rgba(56, 189, 248, 0.2);
}

.popular-tag {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--primary-sky), var(--primary-indigo));
  color: #fff;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: 20px;
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(56, 189, 248, 0.4);
}

.plan-title {
  font-size: 1.35rem;
  font-weight: 800;
  margin-bottom: 6px;
  color: #fff;
}

.plan-subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
  min-height: 40px;
  margin-bottom: 20px;
}

.plan-price-box {
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.plan-price {
  font-size: 2.25rem;
  font-weight: 900;
  color: var(--primary-sky);
}

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

.plan-features {
  list-style: none;
  margin-bottom: 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-sub);
}

.plan-features svg {
  width: 18px;
  height: 18px;
  color: var(--accent-green);
  flex-shrink: 0;
}

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

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: transform var(--transition-fast);
}

.testimonial-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-glow);
}

.testimonial-stars {
  color: #f59e0b;
  font-size: 1.1rem;
  margin-bottom: 12px;
}

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

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

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-sky), var(--primary-indigo));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #fff;
}

.user-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
}

.user-info span {
  font-size: 0.78rem;
  color: var(--accent-green);
  font-weight: 600;
}

/* FAQ Section */
.faq-wrapper {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

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

.faq-question {
  padding: 22px 24px;
  font-weight: 700;
  font-size: 1.05rem;
  color: #fff;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.faq-icon {
  font-size: 1.2rem;
  transition: transform var(--transition-fast);
  color: var(--primary-sky);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
  padding: 0 24px;
  color: var(--text-muted);
  font-size: 0.96rem;
  line-height: 1.8;
}

.faq-item.active .faq-answer {
  max-height: 300px;
  padding: 0 24px 22px 24px;
}

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

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

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all var(--transition-fast);
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-glow);
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.article-tag {
  background: rgba(56, 189, 248, 0.1);
  color: var(--primary-sky);
  padding: 2px 10px;
  border-radius: 12px;
  font-weight: 600;
}

.article-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.5;
  margin-bottom: 12px;
}

.article-excerpt {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
}

.article-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary-sky);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* Article Detail Page Layout */
.article-page {
  padding: 60px 0;
}

.article-container {
  max-width: 860px;
  margin: 0 auto;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 48px;
}

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

.breadcrumb a {
  color: var(--text-sub);
}

.article-header-title {
  font-size: 2.3rem;
  font-weight: 900;
  line-height: 1.3;
  margin-bottom: 20px;
}

.article-header-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 0.88rem;
  color: var(--text-muted);
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.article-body {
  font-size: 1.05rem;
  line-height: 1.9;
  color: var(--text-sub);
}

.article-body h2 {
  font-size: 1.6rem;
  font-weight: 800;
  color: #fff;
  margin: 36px 0 18px 0;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.article-body h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--primary-sky);
  margin: 28px 0 14px 0;
}

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

.article-body ul, .article-body ol {
  margin: 0 0 24px 24px;
}

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

.article-callout {
  background: rgba(56, 189, 248, 0.08);
  border-left: 4px solid var(--primary-sky);
  padding: 20px 24px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 28px 0;
}

.article-cta-box {
  background: linear-gradient(135deg, rgba(2, 132, 199, 0.15) 0%, rgba(79, 70, 229, 0.15) 100%);
  border: 1px solid var(--border-glow);
  padding: 30px;
  border-radius: var(--radius-md);
  text-align: center;
  margin: 40px 0;
}

.article-cta-box h3 {
  font-size: 1.4rem;
  color: #fff;
  margin-bottom: 10px;
}

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

/* Footer Section */
footer {
  background: #070a12;
  border-top: 1px solid var(--border-color);
  padding: 60px 0 30px 0;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 12px;
  max-width: 320px;
  line-height: 1.6;
}

.footer-col h5 {
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 18px;
}

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

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

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 24px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* Core Task 2: Low-profile PBN Link Section */
.footer-friend-links {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px dashed rgba(255, 255, 255, 0.06);
  text-align: center;
  font-size: 0.8rem;
  color: rgba(148, 163, 184, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-friend-links span {
  font-weight: 600;
  color: rgba(148, 163, 184, 0.5);
}

.footer-friend-links a {
  color: rgba(148, 163, 184, 0.7);
  font-size: 0.8rem;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-friend-links a:hover {
  color: var(--primary-sky);
  text-decoration: underline;
}

/* Mobile Responsive Breakpoints */
@media (max-width: 1024px) {
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .bento-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .bento-card.span-2 {
    grid-column: span 2;
  }

  .testimonials-grid, .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-cta-btn {
    display: none;
  }

  .mobile-menu-toggle {
    display: block;
  }

  .hero-title {
    font-size: 2.25rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .metrics-row {
    grid-template-columns: repeat(2, 1fr);
  }

  .ping-grid {
    grid-template-columns: 1fr;
  }

  .bento-grid {
    grid-template-columns: 1fr;
  }

  .bento-card.span-2 {
    grid-column: span 1;
  }

  .pricing-grid {
    grid-template-columns: 1fr;
  }

  .testimonials-grid, .articles-grid {
    grid-template-columns: 1fr;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .article-container {
    padding: 24px 18px;
  }

  .article-header-title {
    font-size: 1.75rem;
  }
}