/* 
  Yueto Landing Page Style Sheet
  Theme: Aviation/Flight, Futuristic Dark Mode
*/

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

:root {
  --bg-primary: #0a0f1d;
  --bg-secondary: #111827;
  --text-primary: #f3f4f6;
  --text-secondary: #9ca3af;
  --accent-blue: #0ea5e9;
  --accent-cyan: #06b6d4;
  --accent-purple: #8b5cf6;
  --accent-orange: #f97316;
  --glow-color: rgba(14, 165, 233, 0.4);
  --glass-bg: rgba(17, 24, 39, 0.7);
  --glass-border: rgba(255, 255, 255, 0.08);
  --font-title: 'Outfit', 'Noto Sans SC', sans-serif;
  --font-body: 'Noto Sans SC', 'Outfit', sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  cursor: none; /* Hide default cursor to use trailing cursor */
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
  background: var(--accent-blue);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent-cyan);
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-body);
  overflow-x: hidden;
  line-height: 1.6;
}

/* Custom Cursor Tail Styling */
#custom-cursor {
  width: 12px;
  height: 12px;
  background: var(--accent-cyan);
  border-radius: 50%;
  position: fixed;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 9999;
  mix-blend-mode: screen;
  transition: transform 0.1s ease;
  box-shadow: 0 0 10px var(--accent-cyan);
}

.cursor-tail {
  width: 8px;
  height: 8px;
  background: var(--accent-blue);
  border-radius: 50%;
  position: fixed;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 9998;
  opacity: 0.7;
  transition: transform 0.05s linear;
}

/* Make sure active elements show custom hover state */
a, button, select, input, .faq-header, .pricing-tab {
  cursor: none;
}

/* Background Airplane Elements */
.bg-sky-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.bg-star {
  position: absolute;
  background: white;
  border-radius: 50%;
  animation: shine 3s infinite ease-in-out;
}

.bg-airplane {
  position: absolute;
  width: 30px;
  height: 30px;
  opacity: 0.15;
  filter: drop-shadow(0 0 8px var(--accent-cyan));
  animation: flight-path 25s infinite linear;
}

/* Keyframes */
@keyframes shine {
  0%, 100% { opacity: 0.2; }
  50% { opacity: 0.8; }
}

@keyframes flight-path {
  0% {
    transform: translate(-10%, 110%) rotate(45deg);
  }
  50% {
    transform: translate(60%, 50%) rotate(40deg);
  }
  100% {
    transform: translate(110%, -10%) rotate(45deg);
  }
}

/* Glassmorphism Classes */
.glass-panel {
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: 20px;
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.glass-panel:hover {
  border-color: rgba(14, 165, 233, 0.3);
  box-shadow: 0 8px 32px 0 rgba(14, 165, 233, 0.15);
}

/* Navigation */
header {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 100;
  background: rgba(10, 15, 29, 0.8);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--glass-border);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.2rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: var(--font-title);
  font-size: 1.8rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--text-primary) 30%, var(--accent-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo svg {
  fill: var(--accent-cyan);
  width: 28px;
  height: 28px;
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-6px) rotate(5deg); }
}

nav ul {
  display: flex;
  list-style: none;
  gap: 2rem;
}

nav a {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  transition: color 0.3s;
  font-size: 1rem;
}

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

.btn-register {
  background: linear-gradient(135deg, var(--accent-blue) 0%, var(--accent-cyan) 100%);
  color: white;
  border: none;
  padding: 0.6rem 1.5rem;
  border-radius: 50px;
  font-family: var(--font-title);
  font-weight: 600;
  box-shadow: 0 4px 15px var(--glow-color);
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
  text-align: center;
}

.btn-register:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(14, 165, 233, 0.6);
  background: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-blue) 100%);
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8rem 2rem 4rem 2rem;
  position: relative;
  text-align: center;
  background: radial-gradient(circle at 50% 30%, rgba(14, 165, 233, 0.15), transparent 60%);
}

.hero-content {
  max-width: 800px;
  z-index: 1;
}

.badge {
  background: rgba(14, 165, 233, 0.1);
  border: 1px solid rgba(14, 165, 233, 0.3);
  padding: 0.5rem 1.2rem;
  border-radius: 50px;
  color: var(--accent-cyan);
  font-weight: 600;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 2rem;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.9; box-shadow: 0 0 0 0 rgba(6, 182, 212, 0.4); }
  50% { opacity: 1; box-shadow: 0 0 10px 4px rgba(6, 182, 212, 0.2); }
}

h1 {
  font-family: var(--font-title);
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}

.gradient-text {
  background: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 3rem auto;
}

.cta-group {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  padding: 0.6rem 1.5rem;
  border-radius: 50px;
  font-family: var(--font-title);
  font-weight: 600;
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--text-secondary);
}

/* Features Section */
.section-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 6rem 2rem;
}

.section-title {
  text-align: center;
  font-family: var(--font-title);
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 4rem;
  font-size: 1.1rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.feature-card {
  padding: 2.5rem;
  text-align: left;
  position: relative;
  overflow: hidden;
}

.feature-icon {
  width: 60px;
  height: 60px;
  background: rgba(14, 165, 233, 0.1);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  color: var(--accent-cyan);
}

.feature-icon svg {
  width: 30px;
  height: 30px;
  fill: currentColor;
}

.feature-card h3 {
  font-family: var(--font-title);
  font-size: 1.4rem;
  margin-bottom: 1rem;
}

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

/* Pricing Index Section (价格检索) */
.pricing-section {
  background: linear-gradient(180deg, transparent, rgba(14, 165, 233, 0.05) 50%, transparent);
}

.pricing-search-box {
  max-width: 600px;
  margin: 0 auto 3rem auto;
  display: flex;
  gap: 1rem;
}

.pricing-search-box select, .pricing-search-box input {
  flex: 1;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  color: var(--text-primary);
  padding: 0.8rem 1.2rem;
  font-size: 1rem;
  outline: none;
  transition: all 0.3s;
}

.pricing-search-box select:focus, .pricing-search-box input:focus {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.3);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-bottom: 3rem;
}

.price-card {
  padding: 3rem 2rem;
  text-align: center;
  position: relative;
  border-radius: 24px;
}

.price-card.featured {
  border-color: var(--accent-cyan);
  box-shadow: 0 8px 32px 0 rgba(6, 182, 212, 0.2);
}

.ribbon {
  position: absolute;
  top: 15px;
  right: 15px;
  background: var(--accent-cyan);
  color: #0a0f1d;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 0.2rem 0.8rem;
  border-radius: 20px;
  text-transform: uppercase;
}

.price-card h3 {
  font-family: var(--font-title);
  font-size: 1.6rem;
  margin-bottom: 1rem;
}

.price-value {
  font-family: var(--font-title);
  font-size: 3rem;
  font-weight: 800;
  color: var(--accent-cyan);
  margin-bottom: 0.5rem;
}

.price-value span {
  font-size: 1rem;
  font-weight: 400;
  color: var(--text-secondary);
}

.price-description {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.price-features {
  list-style: none;
  text-align: left;
  margin-bottom: 2.5rem;
}

.price-features li {
  margin-bottom: 0.8rem;
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.price-features svg {
  width: 18px;
  height: 18px;
  fill: var(--accent-cyan);
  flex-shrink: 0;
}

/* Article Portal Section */
.articles-section {
  position: relative;
}

.article-card {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  height: 100%;
}

.article-header-img {
  width: 100%;
  height: 180px;
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.1), rgba(139, 92, 246, 0.2));
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden; /* Ensure rounded corner boundary */
}

.article-header-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.article-card:hover .article-header-img img {
  transform: scale(1.08); /* Premium hover zoom effect */
}

.article-header-img::after {
  content: '✈️';
  font-size: 3rem;
  opacity: 0.3;
}

.article-header-img:has(img)::after {
  display: none; /* Hide placeholder when real image exists */
}

.article-body {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.article-tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.tag {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-secondary);
}

.article-body h3 {
  font-family: var(--font-title);
  font-size: 1.25rem;
  margin-bottom: 0.8rem;
  line-height: 1.4;
}

.article-body h3 a {
  text-decoration: none;
  color: var(--text-primary);
  transition: color 0.3s;
}

.article-body h3 a:hover {
  color: var(--accent-cyan);
}

.article-excerpt {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.article-link {
  color: var(--accent-cyan);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  transition: gap 0.3s;
}

.article-link:hover {
  gap: 0.5rem;
}

/* User Reviews Section */
.reviews-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.review-card {
  padding: 2rem;
  position: relative;
}

.review-stars {
  color: #fbbf24;
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

.review-text {
  font-style: italic;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.reviewer {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.reviewer-avatar {
  width: 45px;
  height: 45px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: white;
  font-family: var(--font-title);
}

.reviewer-info h4 {
  font-family: var(--font-title);
  font-size: 1rem;
  margin-bottom: 0.1rem;
}

.reviewer-info p {
  color: var(--text-secondary);
  font-size: 0.8rem;
}

/* FAQ Section */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  margin-bottom: 1rem;
}

.faq-header {
  padding: 1.2rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--glass-border);
  transition: all 0.3s;
}

.faq-header:hover {
  background: rgba(255, 255, 255, 0.05);
}

.faq-header h3 {
  font-size: 1.1rem;
  font-weight: 600;
}

.faq-icon {
  font-size: 1.2rem;
  transition: transform 0.3s;
}

.faq-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s;
  padding: 0 1.5rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
  border-bottom-left-radius: 12px;
  border-bottom-right-radius: 12px;
}

.faq-item.active .faq-header {
  border-bottom-left-radius: 0;
  border-bottom-right-radius: 0;
  border-color: rgba(6, 182, 212, 0.3);
}

.faq-item.active .faq-content {
  max-height: 200px;
  padding: 1rem 1.5rem 1.5rem 1.5rem;
  background: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--glass-border);
  border-top: none;
  border-color-top: transparent;
  border-bottom-left-radius: 12px;
  border-bottom-right-radius: 12px;
}

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

/* Call to Action */
.cta-banner {
  background: radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.15), transparent 50%),
              radial-gradient(circle at 20% 80%, rgba(14, 165, 233, 0.15), transparent 50%);
  text-align: center;
  padding: 5rem 2rem;
  border-radius: 30px;
  margin-top: 4rem;
  position: relative;
  overflow: hidden;
}

.cta-banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border-radius: 30px;
  border: 1px solid rgba(255, 255, 255, 0.05);
  pointer-events: none;
}

.cta-banner h2 {
  font-family: var(--font-title);
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.cta-banner p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto 2.5rem auto;
}

/* Article Detail Page Styling */
.article-page {
  padding-top: 8rem;
}

.article-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem;
}

.article-meta {
  margin-bottom: 2rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.article-content {
  font-size: 1.1rem;
  line-height: 1.8;
  color: #e5e7eb;
}

.article-content p {
  margin-bottom: 1.5rem;
}

.article-content h2 {
  font-family: var(--font-title);
  font-size: 1.8rem;
  margin: 2.5rem 0 1.2rem 0;
  color: var(--accent-cyan);
}

.article-content h3 {
  font-family: var(--font-title);
  font-size: 1.4rem;
  margin: 2rem 0 1rem 0;
  color: var(--text-primary);
}

.article-content a {
  color: var(--accent-cyan);
  text-decoration: underline;
  cursor: none;
}

.article-content a:hover {
  color: var(--accent-blue);
}

.article-navigation {
  display: flex;
  justify-content: space-between;
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--glass-border);
}

.article-nav-btn {
  max-width: 45%;
  text-decoration: none;
}

.article-nav-btn span {
  display: block;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.3rem;
}

.article-nav-btn p {
  font-size: 0.95rem;
  color: var(--accent-cyan);
  font-weight: 600;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.article-nav-btn:hover p {
  color: var(--accent-blue);
}

/* Footer Section - PBN weight delivery pipeline */
footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--glass-border);
  padding: 4rem 2rem 2rem 2rem;
  text-align: center;
  position: relative;
  z-index: 10;
}

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

.footer-logo {
  font-family: var(--font-title);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 1rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
  max-width: 400px;
  margin: 0 auto 2rem auto;
}

.footer-copyright {
  color: var(--text-secondary);
  font-size: 0.85rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 2rem;
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

/* High energy weight transmission - PBN links styles */
.footer-pbn-links {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  align-items: center;
  font-size: 0.75rem; /* Low key, blending design as requested */
  color: rgba(156, 163, 175, 0.3); /* Subtle blend color */
}

.footer-pbn-links a {
  color: rgba(156, 163, 175, 0.4); /* Fades into background slightly */
  text-decoration: none;
  font-weight: 400;
  transition: color 0.3s;
}

.footer-pbn-links a:hover {
  color: var(--accent-cyan); /* Glow on hover */
}

/* Responsive Rules */
@media (max-width: 768px) {
  * {
    cursor: auto !important; /* Enable normal cursor on mobile */
  }
  
  #custom-cursor, .cursor-tail {
    display: none !important; /* Hide custom cursor on mobile */
  }

  h1 {
    font-size: 2.5rem;
  }

  .section-title {
    font-size: 2rem;
  }

  nav ul {
    display: none; /* In production we would add burger menu, but for simple landing page we prioritize main items or register buttons */
  }

  .pricing-search-box {
    flex-direction: column;
  }

  .cta-group {
    flex-direction: column;
    align-items: stretch;
    padding: 0 2rem;
  }

  .article-navigation {
    flex-direction: column;
    gap: 1.5rem;
  }

  .article-nav-btn {
    max-width: 100%;
  }
}