/* ==========================================================================
   冲上云霄云机场官网 - 核心样式文件
   Domain: chongshangyunxiao.homes
   Theme: Mint/Emerald Green (#20c997)
   ========================================================================== */

:root {
  --primary-color: #20c997;
  --primary-hover: #1baa80;
  --primary-light: #e6f9f3;
  --secondary-color: #0f172a;
  --text-dark: #1e293b;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --bg-light: #f8fafc;
  --bg-white: #ffffff;
  --border-color: #e2e8f0;
  --shadow-sm: 0 2px 8px rgba(32, 201, 151, 0.08);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.08);
  --shadow-hover: 0 12px 32px rgba(32, 201, 151, 0.18);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  color: var(--text-dark);
  background-color: var(--bg-white);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
}

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

a:hover {
  color: var(--primary-hover);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Utility Classes */
.text-center { text-align: center; }
.text-primary { color: var(--primary-color); }
.bg-light { background-color: var(--bg-light); }

.section-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--secondary-color);
  margin-bottom: 12px;
  text-align: center;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  text-align: center;
  max-width: 680px;
  margin: 0 auto 48px auto;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--primary-color);
  color: #ffffff;
  border-color: var(--primary-color);
  box-shadow: 0 4px 14px rgba(32, 201, 151, 0.35);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  border-color: var(--primary-hover);
  color: #ffffff;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(32, 201, 151, 0.45);
}

.btn-outline {
  background-color: transparent;
  color: var(--primary-color);
  border-color: var(--primary-color);
}

.btn-outline:hover {
  background-color: var(--primary-light);
  color: var(--primary-hover);
  transform: translateY(-2px);
}

.btn-recommend {
  background: linear-gradient(135deg, #10b981 0%, #059669 100%);
  color: #ffffff !important;
  font-weight: 700;
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.btn-recommend:hover {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(16, 185, 129, 0.45);
}

/* Header & Nav */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  padding: 16px 0;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-logo-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--secondary-color);
  font-size: 1.25rem;
  font-weight: 700;
}

.brand-logo-img {
  width: 38px;
  height: 38px;
  object-fit: contain;
}

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

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

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

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

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--text-dark);
  cursor: pointer;
}

/* Hero Section */
.hero-section {
  padding: 80px 0 100px 0;
  background: linear-gradient(180deg, #ffffff 0%, #f4fbf8 100%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background-color: var(--primary-light);
  color: var(--primary-color);
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: 50px;
  margin-bottom: 16px;
}

.hero-title {
  font-size: 2.75rem;
  font-weight: 800;
  color: var(--secondary-color);
  line-height: 1.25;
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  margin-bottom: 32px;
  line-height: 1.7;
}

.hero-buttons {
  display: grid;
  grid-template-columns: repeat(2, minmax(140px, 180px));
  gap: 16px;
  margin-bottom: 28px;
}

.hero-stats {
  display: flex;
  gap: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.stat-item h4 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.stat-item p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-illustration {
  position: relative;
  display: flex;
  justify-content: center;
}

.hero-card-img {
  width: 100%;
  max-width: 520px;
  border-radius: var(--radius-lg);
  box-shadow: 0 20px 40px rgba(32, 201, 151, 0.12);
  background-color: #ffffff;
}

/* Advantages Section */
.advantages-section {
  padding: 90px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

.feature-card {
  background-color: var(--bg-white);
  padding: 32px 24px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--primary-color);
}

.feature-icon {
  width: 54px;
  height: 54px;
  border-radius: 12px;
  background-color: var(--primary-light);
  color: var(--primary-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--secondary-color);
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Pricing Section */
.pricing-section {
  padding: 90px 0;
  background-color: var(--bg-light);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 28px;
}

.pricing-card {
  background-color: var(--bg-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  padding: 36px 28px;
  position: relative;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

.pricing-card.featured {
  border: 2px solid var(--primary-color);
  box-shadow: var(--shadow-hover);
  transform: scale(1.03);
}

.pricing-badge {
  position: absolute;
  top: -14px;
  right: 20px;
  background-color: var(--primary-color);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 50px;
  text-transform: uppercase;
}

.pricing-card h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--secondary-color);
  margin-bottom: 8px;
}

.pricing-card .price {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--primary-color);
  margin-bottom: 16px;
}

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

.pricing-features {
  list-style: none;
  margin: 24px 0 32px 0;
  flex-grow: 1;
}

.pricing-features li {
  padding: 8px 0;
  font-size: 0.95rem;
  color: var(--text-dark);
  display: flex;
  align-items: center;
  gap: 8px;
}

.pricing-features li::before {
  content: "✓";
  color: var(--primary-color);
  font-weight: bold;
}

/* Articles Directory Section */
.articles-section {
  padding: 90px 0;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 28px;
}

.article-card {
  background-color: var(--bg-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  padding: 28px;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

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

.article-tag {
  display: inline-block;
  padding: 4px 10px;
  background-color: var(--primary-light);
  color: var(--primary-color);
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 4px;
  margin-bottom: 12px;
  align-self: flex-start;
}

.article-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--secondary-color);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-light);
  border-top: 1px solid var(--border-color);
  padding-top: 12px;
}

/* User Reviews Section */
.reviews-section {
  padding: 90px 0;
  background-color: var(--bg-light);
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.review-card {
  background-color: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 28px;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.review-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.review-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: var(--primary-color);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
}

.review-user-info h4 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--secondary-color);
}

.review-user-info p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 12px;
  font-size: 0.9rem;
}

.review-content {
  color: var(--text-dark);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* FAQ Section */
.faq-section {
  padding: 90px 0;
}

.faq-accordion {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  background-color: var(--bg-white);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  background: none;
  border: none;
  text-align: left;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--secondary-color);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-question::after {
  content: "+";
  font-size: 1.5rem;
  color: var(--primary-color);
  transition: var(--transition);
}

.faq-item.active .faq-question::after {
  content: "−";
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out;
  padding: 0 24px;
  background-color: #fafbfc;
}

.faq-item.active .faq-answer {
  padding: 0 24px 20px 24px;
  max-height: 400px;
}

.faq-answer p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

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

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

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

.article-header {
  margin-bottom: 32px;
}

.article-header h1 {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--secondary-color);
  line-height: 1.3;
  margin-bottom: 16px;
}

.article-meta-info {
  display: flex;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--text-light);
}

.article-content {
  background-color: var(--bg-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  padding: 40px;
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-dark);
}

.article-content h2 {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--secondary-color);
  margin: 32px 0 16px 0;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-light);
}

.article-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--secondary-color);
  margin: 24px 0 12px 0;
}

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

.article-content ul, .article-content ol {
  margin: 16px 0 20px 24px;
}

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

.article-callout {
  background-color: var(--primary-light);
  border-left: 4px solid var(--primary-color);
  padding: 20px;
  border-radius: var(--radius-sm);
  margin: 24px 0;
}

.related-articles {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
}

/* Footer & PBN Links (Core Task 2) */
.site-footer {
  background-color: #0f172a;
  color: #94a3b8;
  padding: 60px 0 30px 0;
  font-size: 0.9rem;
}

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

.footer-brand h3 {
  color: #ffffff;
  font-size: 1.2rem;
  margin-bottom: 12px;
}

.footer-brand p {
  color: #64748b;
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-col h4 {
  color: #ffffff;
  font-size: 1rem;
  margin-bottom: 16px;
}

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

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

.footer-col a {
  color: #94a3b8;
}

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

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 24px;
  text-align: center;
}

/* Low-profile Friendly Links Section (PBN Target Injection) */
.friendly-links-area {
  margin-top: 16px;
  padding-top: 12px;
  font-size: 0.8rem;
  color: #64748b;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.friendly-links-title {
  color: #475569;
  font-size: 0.8rem;
}

.friendly-links-area a {
  color: #64748b;
  text-decoration: none;
  font-size: 0.8rem;
  transition: color 0.2s ease;
}

.friendly-links-area a:hover {
  color: var(--primary-color);
}

/* Responsive Breakdown */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .hero-buttons {
    justify-content: center;
  }
  .hero-stats {
    justify-content: center;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .pricing-card.featured {
    transform: none;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .mobile-toggle {
    display: block;
  }
  .hero-title {
    font-size: 2rem;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .article-content {
    padding: 20px;
  }
}