/* 酷酷云机场 - 灰色系炫酷科技风样式表 */
:root {
  --bg-primary: #14161a;
  --bg-secondary: #1b1e25;
  --bg-card: #20242d;
  --bg-card-hover: #272c38;
  --border-color: #2d3340;
  --border-glow: #384152;
  
  --text-primary: #f0f2f5;
  --text-secondary: #a0a7b5;
  --text-muted: #6c7585;
  
  --accent-cyan: #00f2fe;
  --accent-blue: #4facfe;
  --accent-purple: #9d4edd;
  --accent-gradient: linear-gradient(135deg, #00f2fe 0%, #4facfe 50%, #9d4edd 100%);
  --accent-glow: 0 0 20px rgba(0, 242, 254, 0.25);
  --btn-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --btn-hover-gradient: linear-gradient(135deg, #00f2fe 0%, #4facfe 100%);
  
  --font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --container-width: 1200px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: var(--font-family);
  -webkit-font-smoothing: antialiased;
}

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

body {
  overflow-x: hidden;
  background: radial-gradient(circle at 50% 0%, rgba(0, 242, 254, 0.05) 0%, transparent 60%),
              radial-gradient(circle at 90% 40%, rgba(157, 78, 221, 0.04) 0%, transparent 50%),
              var(--bg-primary);
  min-height: 100vh;
  font-weight: 300;
  letter-spacing: 0.3px;
}

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

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header & Nav */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(20, 22, 26, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(45, 51, 64, 0.6);
  height: 72px;
  display: flex;
  align-items: center;
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.25rem;
  font-weight: 400;
  letter-spacing: 0.5px;
  color: var(--text-primary);
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--accent-gradient);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--accent-glow);
}

.logo-icon svg {
  width: 22px;
  height: 22px;
  fill: #fff;
}

.logo span {
  font-weight: 600;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

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

.nav-link {
  font-size: 0.95rem;
  font-weight: 300;
  color: var(--text-secondary);
  position: relative;
  padding: 6px 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--accent-cyan);
}

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

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

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 400;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--btn-gradient);
  color: #0b0f19;
  font-weight: 500;
  box-shadow: 0 4px 20px rgba(0, 242, 254, 0.25);
}

.btn-primary:hover {
  background: var(--btn-hover-gradient);
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(0, 242, 254, 0.4);
}

.btn-outline {
  background: rgba(32, 36, 45, 0.6);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
}

.btn-outline:hover {
  border-color: var(--accent-cyan);
  background: rgba(0, 242, 254, 0.08);
  color: var(--accent-cyan);
}

.btn-lg {
  padding: 14px 36px;
  font-size: 1.05rem;
  border-radius: 14px;
}

/* Mobile Nav Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 6px;
}

.mobile-toggle svg {
  width: 26px;
  height: 26px;
}

/* Hero Section */
.hero {
  padding: 160px 0 100px;
  position: relative;
  overflow: hidden;
  text-align: center;
  background: radial-gradient(ellipse at 50% 10%, rgba(0, 242, 254, 0.12) 0%, rgba(20, 22, 26, 0.95) 70%);
}

.hero-glow-element {
  position: absolute;
  top: 15%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 300px;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.15) 0%, rgba(157, 78, 221, 0.08) 50%, transparent 70%);
  filter: blur(60px);
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 900px;
  margin: 0 auto;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: 30px;
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.25);
  color: var(--accent-cyan);
  font-size: 0.85rem;
  font-weight: 300;
  margin-bottom: 24px;
  letter-spacing: 0.5px;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 10px var(--accent-cyan);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { opacity: 0.4; }
  50% { opacity: 1; }
  100% { opacity: 0.4; }
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 300;
  line-height: 1.25;
  margin-bottom: 24px;
  color: #ffffff;
  letter-spacing: 0.5px;
}

.hero-title span {
  font-weight: 500;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.15rem;
  font-weight: 300;
  color: var(--text-secondary);
  max-width: 720px;
  margin: 0 auto 40px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin-bottom: 60px;
}

.hero-features-list {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 40px;
}

.hero-feat-card {
  background: rgba(32, 36, 45, 0.5);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
  padding: 24px 20px;
  border-radius: var(--radius-md);
  text-align: left;
  transition: var(--transition);
}

.hero-feat-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
  background: rgba(39, 44, 56, 0.7);
  box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

.feat-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(0, 242, 254, 0.1);
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.feat-title {
  font-size: 1.05rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.feat-desc {
  font-size: 0.88rem;
  font-weight: 300;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Common Section Layout */
.section {
  padding: 100px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 60px;
}

.section-tag {
  color: var(--accent-cyan);
  font-size: 0.9rem;
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 12px;
  display: block;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 300;
  color: #fff;
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}

.section-title strong {
  font-weight: 500;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-desc {
  font-size: 1rem;
  font-weight: 300;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* Grid & Cards */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

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

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card:hover {
  border-color: rgba(0, 242, 254, 0.4);
  transform: translateY(-5px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}

.card-glow {
  position: absolute;
  top: 0;
  right: 0;
  width: 150px;
  height: 150px;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.1) 0%, transparent 70%);
  pointer-events: none;
}

/* Pricing Section */
.pricing-card {
  display: flex;
  flex-direction: column;
  height: 100%;
  position: relative;
}

.pricing-card.featured {
  border-color: var(--accent-cyan);
  background: linear-gradient(180deg, rgba(0, 242, 254, 0.08) 0%, var(--bg-card) 100%);
}

.popular-badge {
  position: absolute;
  top: 18px;
  right: 20px;
  background: var(--btn-gradient);
  color: #0b0f19;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 20px;
  text-transform: uppercase;
}

.plan-name {
  font-size: 1.3rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.plan-price {
  font-size: 2.5rem;
  font-weight: 300;
  color: #fff;
  margin-bottom: 8px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.plan-price span {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.plan-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

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

.plan-features li {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.92rem;
  color: var(--text-secondary);
  margin-bottom: 14px;
  font-weight: 300;
}

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

/* Target Audience Cards */
.audience-card {
  padding: 28px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: var(--transition);
}

.audience-card:hover {
  border-color: var(--accent-blue);
  background: var(--bg-card);
}

.audience-icon {
  width: 48px;
  height: 48px;
  background: rgba(79, 172, 254, 0.12);
  border-radius: 12px;
  color: var(--accent-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

/* Tutorial Section Tabs & Code */
.tutorial-container {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px;
}

.tutorial-tabs {
  display: flex;
  gap: 12px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 16px;
  margin-bottom: 28px;
  overflow-x: auto;
}

.tab-btn {
  background: rgba(32, 36, 45, 0.5);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 10px 22px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.92rem;
  font-weight: 300;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
}

.tab-btn:hover, .tab-btn.active {
  background: rgba(0, 242, 254, 0.12);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

.step-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.step-item {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.step-number {
  width: 36px;
  height: 36px;
  background: var(--accent-gradient);
  color: #0b0f19;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  flex-shrink: 0;
}

.step-body h4 {
  font-size: 1.1rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.step-body p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* User Reviews */
.review-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #0b0f19;
  font-weight: 600;
}

.user-info h5 {
  font-size: 1rem;
  font-weight: 400;
  color: var(--text-primary);
}

.user-info span {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.review-text {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.7;
  font-style: italic;
}

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

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

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

.faq-question {
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 400;
  color: var(--text-primary);
}

.faq-toggle-icon {
  width: 20px;
  height: 20px;
  color: var(--accent-cyan);
  transition: transform 0.3s ease;
}

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

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s cubic-bezier(0, 1, 0, 1);
  background: rgba(20, 22, 26, 0.4);
}

.faq-answer-inner {
  padding: 0 24px 20px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  border-top: 1px solid rgba(45, 51, 64, 0.4);
  padding-top: 16px;
}

/* Article Cards */
.article-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

.article-card:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-4px);
}

.article-body {
  padding: 24px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.article-tag {
  font-size: 0.8rem;
  color: var(--accent-cyan);
  margin-bottom: 10px;
  display: inline-block;
}

.article-title {
  font-size: 1.15rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-excerpt {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-color);
  padding-top: 14px;
}

/* Article Detail Page Layout */
.article-layout {
  padding: 140px 0 100px;
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 40px;
}

.article-main {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
}

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

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

.article-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

.article-header h1 {
  font-size: 2.2rem;
  font-weight: 300;
  color: #fff;
  margin-bottom: 16px;
  line-height: 1.3;
}

.article-header-meta {
  display: flex;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.article-content {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.85;
}

.article-content h2 {
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--text-primary);
  margin: 36px 0 18px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 400;
  color: var(--text-primary);
  margin: 28px 0 14px;
}

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

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

.article-content li {
  margin-bottom: 10px;
}

.article-content blockquote {
  border-left: 4px solid var(--accent-cyan);
  background: rgba(0, 242, 254, 0.05);
  padding: 16px 20px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 24px 0;
  color: var(--text-primary);
}

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
}

.article-content th, .article-content td {
  border: 1px solid var(--border-color);
  padding: 12px 16px;
  text-align: left;
}

.article-content th {
  background: var(--bg-card);
  color: var(--text-primary);
  font-weight: 400;
}

.cta-box {
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.1) 0%, rgba(157, 78, 221, 0.1) 100%);
  border: 1px solid var(--accent-cyan);
  border-radius: var(--radius-md);
  padding: 32px;
  text-align: center;
  margin: 40px 0;
}

.cta-box h3 {
  font-size: 1.4rem;
  color: #fff;
  margin-bottom: 12px;
  font-weight: 400;
}

.cta-box p {
  color: var(--text-secondary);
  margin-bottom: 20px;
}

/* Sidebar */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.sidebar-widget {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
}

.widget-title {
  font-size: 1.1rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
}

.related-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.related-list li a {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
  display: block;
}

.related-list li a:hover {
  color: var(--accent-cyan);
}

/* Footer */
.footer {
  background: #0f1114;
  border-top: 1px solid var(--border-color);
  padding: 80px 0 40px;
  color: var(--text-secondary);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 60px;
}

.footer-about p {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-top: 16px;
  max-width: 340px;
}

.footer-column h4 {
  font-size: 1rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

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

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

.footer-bottom {
  border-top: 1px solid rgba(45, 51, 64, 0.6);
  padding-top: 28px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Responsive Media Queries */
@media (max-width: 1024px) {
  .hero-title { font-size: 2.6rem; }
  .hero-features-list { grid-template-columns: repeat(2, 1fr); }
  .grid-4, .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .article-layout { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .header .nav-menu {
    position: fixed;
    top: 72px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 72px);
    background: var(--bg-primary);
    flex-direction: column;
    padding: 40px;
    transition: var(--transition);
    align-items: flex-start;
  }
  .header .nav-menu.active {
    left: 0;
  }
  .mobile-toggle { display: block; }
  .hero-title { font-size: 2rem; }
  .hero-subtitle { font-size: 1rem; }
  .hero-actions { flex-direction: column; }
  .hero-features-list { grid-template-columns: 1fr; }
  .grid-3, .grid-4, .grid-2 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 16px; text-align: center; }
}