/* ===== 快连官网 - 全局样式 ===== */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #60a5fa;
  --accent: #06b6d4;
  --bg-dark: #0f172a;
  --bg-card: #1e293b;
  --bg-section: #f8fafc;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-light: #94a3b8;
  --text-white: #f1f5f9;
  --border: #e2e8f0;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow: 0 4px 24px rgba(0,0,0,.06);
  --shadow-lg: 0 12px 48px rgba(0,0,0,.1);
  --transition: .3s cubic-bezier(.4,0,.2,1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text-primary);
  line-height: 1.7;
  background: #fff;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }
ul { list-style: none; }

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

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  line-height: 1.4;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--primary-dark);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(37,99,235,.35);
}
.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}
.btn-outline:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
}
.btn-lg { padding: 16px 40px; font-size: 1.125rem; }

/* ===== Header ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.375rem;
  font-weight: 800;
  color: var(--text-primary);
}
.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1.125rem;
  font-weight: 700;
}
.nav { display: flex; align-items: center; gap: 32px; }
.nav a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: .9375rem;
  position: relative;
}
.nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: var(--transition);
}
.nav a:hover { color: var(--primary); }
.nav a:hover::after { width: 100%; }
.nav a.active { color: var(--primary); }
.nav a.active::after { width: 100%; }

.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
  background: none;
  border: none;
}
.mobile-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-dark);
  color: var(--text-light);
  padding: 60px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand .logo { color: #fff; margin-bottom: 16px; }
.footer-brand p { font-size: .875rem; line-height: 1.8; max-width: 320px; }
.footer h4 { color: #fff; font-size: .9375rem; margin-bottom: 16px; }
.footer a { color: var(--text-light); font-size: .875rem; display: block; margin-bottom: 10px; }
.footer a:hover { color: var(--primary-light); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  font-size: .8125rem;
}

/* ===== Hero Section ===== */
.hero {
  padding: 100px 0 80px;
  background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #0f172a 100%);
  color: #fff;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 50%, rgba(37,99,235,.15) 0%, transparent 50%),
              radial-gradient(circle at 70% 50%, rgba(6,182,212,.1) 0%, transparent 50%);
  animation: heroGlow 8s ease-in-out infinite alternate;
}
@keyframes heroGlow {
  from { transform: translate(0,0); }
  to { transform: translate(-2%,-2%); }
}
.hero .container { position: relative; z-index: 1; }
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 16px;
  border-radius: 100px;
  background: rgba(37,99,235,.2);
  border: 1px solid rgba(37,99,235,.3);
  font-size: .8125rem;
  color: var(--primary-light);
  margin-bottom: 24px;
}
.hero h1 {
  font-size: 3.25rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 20px;
  letter-spacing: -.02em;
}
.hero h1 span {
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero p {
  font-size: 1.1875rem;
  color: var(--text-light);
  max-width: 640px;
  margin: 0 auto 36px;
  line-height: 1.8;
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 60px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,.08);
}
.hero-stat { text-align: center; }
.hero-stat-number {
  font-size: 2rem;
  font-weight: 800;
  color: #fff;
}
.hero-stat-label {
  font-size: .8125rem;
  color: var(--text-light);
  margin-top: 4px;
}

/* ===== Section通用 ===== */
.section { padding: 80px 0; }
.section-alt { background: var(--bg-section); }
.section-dark {
  background: var(--bg-dark);
  color: #fff;
}
.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 12px;
  letter-spacing: -.01em;
}
.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  text-align: center;
  max-width: 560px;
  margin: 0 auto 48px;
}
.section-dark .section-subtitle { color: var(--text-light); }

/* ===== Features Grid ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.feature-card {
  background: #fff;
  padding: 36px 28px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid var(--border);
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}
.feature-icon.blue { background: #dbeafe; }
.feature-icon.cyan { background: #cffafe; }
.feature-icon.green { background: #d1fae5; }
.feature-icon.purple { background: #e9d5ff; }
.feature-icon.orange { background: #fed7aa; }
.feature-icon.red { background: #fecaca; }
.feature-card h3 { font-size: 1.1875rem; margin-bottom: 10px; }
.feature-card p { color: var(--text-secondary); font-size: .9375rem; line-height: 1.7; }

/* ===== Download Section / Platform Cards ===== */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
}
.download-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
  box-shadow: var(--shadow);
}
.download-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.download-icon {
  font-size: 3rem;
  margin-bottom: 16px;
  line-height: 1;
}
.download-card h3 { font-size: 1.125rem; margin-bottom: 6px; }
.download-card p { color: var(--text-secondary); font-size: .8125rem; margin-bottom: 20px; }
.download-card .btn { width: 100%; justify-content: center; }
.version-info {
  margin-top: 48px;
  text-align: center;
  padding: 24px;
  background: var(--bg-section);
  border-radius: var(--radius);
  font-size: .875rem;
  color: var(--text-secondary);
}

/* ===== FAQ ===== */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}
.faq-item:hover { border-color: var(--primary-light); }
.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: none;
  border: none;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  cursor: pointer;
  text-align: left;
  line-height: 1.5;
}
.faq-question::after {
  content: '+';
  font-size: 1.25rem;
  color: var(--primary);
  transition: var(--transition);
  flex-shrink: 0;
}
.faq-item.open .faq-question::after {
  content: '−';
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: var(--transition);
  padding: 0 24px;
  color: var(--text-secondary);
  font-size: .9375rem;
  line-height: 1.8;
}
.faq-item.open .faq-answer {
  max-height: 400px;
  padding: 0 24px 20px;
}

/* ===== About Page ===== */
.about-content {
  max-width: 800px;
  margin: 0 auto;
}
.about-content h2 {
  font-size: 1.5rem;
  margin: 36px 0 16px;
  color: var(--text-primary);
}
.about-content p {
  color: var(--text-secondary);
  font-size: 1rem;
  line-height: 1.9;
  margin-bottom: 16px;
}
.values-grid {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 24px;
  margin: 40px 0;
}
.value-card {
  padding: 28px;
  background: var(--bg-section);
  border-radius: var(--radius);
  text-align: center;
}
.value-card h3 { font-size: 1.0625rem; margin-bottom: 8px; }
.value-card p { font-size: .875rem; margin-bottom: 0; }

/* ===== Contact ===== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
  max-width: 800px;
  margin: 0 auto;
}
.contact-card {
  padding: 28px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-align: center;
}
.contact-card h3 { font-size: 1rem; margin-bottom: 8px; }
.contact-card p { color: var(--text-secondary); font-size: .875rem; }

/* ===== Page Header ===== */
.page-header {
  padding: 60px 0;
  background: linear-gradient(135deg, #0f172a, #1e3a5f);
  color: #fff;
  text-align: center;
}
.page-header h1 { font-size: 2.5rem; font-weight: 800; margin-bottom: 12px; }
.page-header p { color: var(--text-light); font-size: 1.0625rem; max-width: 560px; margin: 0 auto; }

/* ===== Steps ===== */
.steps { display: grid; grid-template-columns: repeat(3,1fr); gap: 28px; counter-reset: step; }
.step-card {
  text-align: center;
  padding: 36px 24px;
  position: relative;
}
.step-card::before {
  counter-increment: step;
  content: '0' counter(step);
  font-size: 3.5rem;
  font-weight: 800;
  color: rgba(37,99,235,.1);
  line-height: 1;
  display: block;
  margin-bottom: 12px;
}
.step-card h3 { font-size: 1.125rem; margin-bottom: 8px; }
.step-card p { color: var(--text-secondary); font-size: .875rem; line-height: 1.7; }

/* ===== Features Detail Page ===== */
.feature-detail { margin-bottom: 60px; }
.feature-detail:last-child { margin-bottom: 0; }
.feature-detail-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.feature-detail.reverse .feature-detail-inner { direction: rtl; }
.feature-detail.reverse .feature-detail-inner > * { direction: ltr; }
.feature-detail-text h2 { font-size: 1.75rem; margin-bottom: 16px; }
.feature-detail-text p { color: var(--text-secondary); font-size: 1rem; line-height: 1.8; margin-bottom: 16px; }
.feature-detail-text ul { margin-top: 16px; }
.feature-detail-text li {
  padding: 8px 0 8px 28px;
  position: relative;
  color: var(--text-secondary);
}
.feature-detail-text li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: #10b981;
  font-weight: 700;
}
.feature-detail-visual {
  background: linear-gradient(135deg, var(--bg-section), #eef2ff);
  border-radius: var(--radius-lg);
  padding: 60px 40px;
  text-align: center;
  font-size: 6rem;
  min-height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ===== CTA ===== */
.cta-section {
  text-align: center;
  padding: 80px 0;
}
.cta-section h2 { font-size: 2rem; margin-bottom: 16px; }
.cta-section p { color: var(--text-light); margin-bottom: 32px; font-size: 1.0625rem; }

/* ===== World Map ===== */
.map-wrapper {
  background: linear-gradient(135deg, #0c1929 0%, #132742 50%, #0c1929 100%);
  border-radius: var(--radius-lg);
  padding: 40px 32px 32px;
  position: relative;
  overflow: hidden;
}
.map-wrapper::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 40%, rgba(37,99,235,.08) 0%, transparent 50%),
    radial-gradient(circle at 70% 60%, rgba(6,182,212,.06) 0%, transparent 50%);
  pointer-events: none;
}
.world-map {
  width: 100%;
  height: auto;
  display: block;
}
.world-map .ocean { fill: #0f1d33; }
.world-map .continent {
  fill: #1a3356;
  transition: fill .4s;
}
.world-map .continent:hover { fill: #23467a; }
.map-node {
  cursor: pointer;
  transition: transform .3s;
}
.map-node:hover { transform: scale(1.5); }
.map-node-dot {
  fill: var(--accent);
  r: 4;
}
.map-node-glow {
  fill: none;
  stroke: var(--accent);
  stroke-width: 2;
  opacity: 0;
}
.map-node:hover .map-node-glow {
  opacity: 1;
  animation: nodePulse 2s ease-in-out infinite;
}
.map-node-dot.highlight { fill: var(--primary-light); r: 5; }
.map-node-label {
  font-size: 9px;
  fill: var(--text-light);
  dominant-baseline: middle;
  text-anchor: start;
}
@keyframes nodePulse {
  0% { r: 6; opacity: .6; }
  50% { r: 16; opacity: 0; }
  100% { r: 6; opacity: .6; }
}
.map-legend {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-top: 24px;
  flex-wrap: wrap;
}
.map-legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: .8125rem;
  color: var(--text-light);
}
.map-legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
}
.map-legend-dot.highlight { background: var(--primary-light); }

/* ===== Breadcrumb ===== */
.breadcrumb {
  padding: 16px 0;
  font-size: .8125rem;
  color: var(--text-light);
}
.breadcrumb a { color: var(--text-light); }
.breadcrumb a:hover { color: var(--primary); }
.breadcrumb span { color: var(--text-secondary); }
.breadcrumb-sep { margin: 0 8px; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .hero h1 { font-size: 2.75rem; }
  .features-grid { grid-template-columns: repeat(2,1fr); }
  .feature-detail-inner { gap: 40px; }
}

@media (max-width: 768px) {
  .nav { display: none; }
  .mobile-toggle { display: flex; }
  .nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: rgba(255,255,255,.98);
    backdrop-filter: blur(12px);
    padding: 24px;
    border-bottom: 1px solid var(--border);
    gap: 20px;
  }

  .hero { padding: 60px 0 50px; }
  .hero h1 { font-size: 2rem; }
  .hero p { font-size: 1rem; }
  .hero-stats { flex-wrap: wrap; gap: 24px; }

  .section { padding: 48px 0; }
  .section-title { font-size: 1.625rem; }

  .features-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .steps { grid-template-columns: 1fr; }
  .values-grid { grid-template-columns: 1fr; }

  .feature-detail-inner { grid-template-columns: 1fr; gap: 24px; }
  .feature-detail.reverse .feature-detail-inner { direction: ltr; }
  .feature-detail-visual { min-height: 200px; padding: 40px 24px; font-size: 4rem; }

  .page-header h1 { font-size: 1.75rem; }
  .download-grid { grid-template-columns: repeat(2,1fr); }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.625rem; }
  .hero-actions { flex-direction: column; align-items: center; }
  .btn-lg { width: 100%; justify-content: center; }
  .download-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
}