* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: #0a0e14;
  color: #c5cdd9;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

.landing { min-height: 100vh; overflow: hidden; background: #0a0e14; }

.landing-nav {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px 40px;
  border-bottom: 1px solid #1f2937;
  background: rgba(10, 14, 20, 0.92);
  backdrop-filter: blur(8px);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #e5e7eb;
  font-size: 16px;
  font-weight: 650;
  text-decoration: none;
}

.nav-icon { font-size: 22px; }
.nav-name { white-space: nowrap; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  color: #9ca3af;
  font-size: 14px;
}

.nav-links a { text-decoration: none; transition: color .15s ease; }
.nav-links a:hover { color: #6ee7b7; }

.nav-cta {
  padding: 8px 18px;
  border-radius: 6px;
  background: linear-gradient(135deg, #3b82f6, #6ee7b7);
  color: #0a0e14 !important;
  font-weight: 650;
}

.hero {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  align-items: center;
  gap: 60px;
  max-width: 1280px;
  margin: 0 auto;
  padding: 84px 60px 104px;
}

.eyebrow {
  margin: 0 0 14px;
  color: #6ee7b7;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .14em;
}

.hero-title {
  margin: 0 0 20px;
  color: #f3f4f6;
  font-size: clamp(42px, 5vw, 58px);
  font-weight: 720;
  letter-spacing: -.035em;
  line-height: 1.08;
}

.hero-gradient {
  background: linear-gradient(135deg, #6ee7b7 0%, #3b82f6 60%, #a78bfa 100%);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  max-width: 560px;
  margin: 0 0 34px;
  color: #9ca3af;
  font-size: 17px;
  line-height: 1.75;
}

.hero-cta, .cta-buttons { display: flex; flex-wrap: wrap; gap: 14px; }
.hero-cta { margin-bottom: 24px; }

.btn-primary-lg, .btn-secondary-lg {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 26px;
  border-radius: 8px;
  font-size: 15px;
  text-decoration: none;
  transition: all .2s ease;
}

.btn-primary-lg {
  box-shadow: 0 4px 16px rgba(110, 231, 183, .2);
  background: linear-gradient(135deg, #3b82f6, #6ee7b7);
  color: #0a0e14;
  font-weight: 650;
}

.btn-primary-lg:hover { transform: translateY(-1px); box-shadow: 0 6px 20px rgba(110, 231, 183, .35); }

.btn-secondary-lg { border: 1px solid #374151; color: #e5e7eb; font-weight: 500; }
.btn-secondary-lg:hover { border-color: #6ee7b7; color: #6ee7b7; }

.hero-meta { display: flex; flex-wrap: wrap; gap: 20px; color: #6b7280; font-size: 13px; }

.hero-visual { display: flex; justify-content: center; }

.demo-card {
  width: 100%;
  max-width: 540px;
  overflow: hidden;
  border: 1px solid #1f2937;
  border-radius: 12px;
  background: #161b22;
  box-shadow: 0 20px 60px rgba(0, 0, 0, .5), 0 0 0 1px rgba(110, 231, 183, .05);
}

.demo-header { display: flex; align-items: center; gap: 8px; padding: 12px 16px; border-bottom: 1px solid #1f2937; background: #0f1419; }
.demo-dot { width: 11px; height: 11px; border-radius: 50%; }
.dot-r { background: #f87171; } .dot-y { background: #fbbf24; } .dot-g { background: #6ee7b7; }
.demo-title { margin-left: 10px; color: #6b7280; font-size: 12px; }
.demo-body { display: flex; flex-direction: column; gap: 14px; padding: 18px; }
.demo-msg { padding: 12px 14px; border-radius: 10px; font-size: 13px; line-height: 1.65; }
.msg-user-demo { align-self: flex-end; max-width: 76%; border-radius: 14px; background: #3b82f6; color: #fff; }
.msg-ai { border: 1px solid #1f2937; background: #0f1419; }
.demo-badges { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 10px; }
.badge { padding: 3px 8px; border-radius: 4px; font-size: 10px; }
.badge-mode { background: rgba(59, 130, 246, .15); color: #93c5fd; }
.badge-conf { background: rgba(110, 231, 183, .15); color: #6ee7b7; }
.badge-src { background: rgba(251, 191, 36, .15); color: #fde68a; }
.demo-summary { color: #c5cdd9; font-size: 13px; line-height: 1.7; }
.demo-summary strong { color: #e5e7eb; }
.demo-trace { margin-top: 10px; padding-top: 10px; border-top: 1px solid #1f2937; color: #6b7280; font-family: monospace; font-size: 11px; }
.demo-trace code { padding: 1px 6px; border-radius: 3px; background: #0a0e14; color: #fde68a; }

.section { max-width: 1280px; margin: 0 auto; padding: 84px 60px; }
.section-alt { max-width: none; background: #0f1419; }
.section-title { margin: 0 0 12px; color: #f3f4f6; font-size: 40px; font-weight: 700; letter-spacing: -.02em; text-align: center; }
.section-subtitle { max-width: 760px; margin: 0 auto 46px; color: #9ca3af; font-size: 17px; text-align: center; }
.section-tagline { margin: 30px 0 0; color: #6ee7b7; font-size: 16px; font-style: italic; text-align: center; }

.compare-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; max-width: 980px; margin: 0 auto; }
.compare-card, .demo-tile, .principle-card { border: 1px solid #1f2937; border-radius: 12px; background: #161b22; }
.compare-card { padding: 32px; }
.compare-card h3 { margin: 0 0 16px; color: #e5e7eb; font-size: 22px; }
.compare-icon { margin-bottom: 12px; color: #6ee7b7; font-size: 28px; }
.compare-card ul { margin: 0; padding: 0; list-style: none; }
.compare-card li { padding: 8px 0; border-bottom: 1px solid rgba(255, 255, 255, .04); color: #9ca3af; font-size: 15px; }
.compare-card li:last-child { border-bottom: 0; }
.compare-good { border-color: rgba(110, 231, 183, .3); background: linear-gradient(135deg, #161b22, rgba(110, 231, 183, .04)); }
.compare-good li { color: #c5cdd9; }
.compare-good li::before { content: "→ "; color: #6ee7b7; }
.compare-bad li::before { content: "· "; color: #6b7280; }

.demo-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; max-width: 1100px; margin: 0 auto; }
.demo-tile { padding: 28px; transition: all .2s ease; }
.demo-tile:hover { border-color: #6ee7b7; transform: translateY(-2px); }
.demo-tile-icon { margin-bottom: 12px; font-size: 36px; }
.demo-tile h3 { margin: 0 0 8px; color: #e5e7eb; font-size: 18px; }
.demo-tile p { min-height: 48px; margin: 0 0 16px; color: #9ca3af; font-size: 14px; line-height: 1.6; }
.demo-code { overflow-x: auto; min-height: 100px; margin: 0; padding: 12px; border: 1px solid #1f2937; border-radius: 6px; background: #0a0e14; color: #9ca3af; font-family: "SF Mono", Consolas, monospace; font-size: 11.5px; line-height: 1.5; white-space: pre-wrap; }

.flow { display: flex; align-items: center; justify-content: center; gap: 10px; max-width: 1120px; margin: 0 auto; }
.flow-step { display: flex; align-items: center; gap: 10px; min-width: 160px; padding: 15px 16px; border: 1px solid #1f2937; border-radius: 10px; background: #161b22; }
.flow-step strong, .flow-step span { display: block; }
.flow-step strong { color: #e5e7eb; font-size: 13px; }
.flow-step span { margin-top: 3px; color: #6b7280; font-size: 11px; line-height: 1.4; }
.flow-icon { font-size: 22px; }
.flow-arrow { color: #4b5563; font-size: 20px; }
.flow-step-final { border-color: rgba(110, 231, 183, .3); background: linear-gradient(135deg, #161b22, rgba(110, 231, 183, .06)); }

.principles-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; max-width: 1100px; margin: 0 auto; }
.principle-card { padding: 24px; text-align: center; transition: all .2s ease; }
.principle-card:hover { border-color: #6ee7b7; transform: translateY(-2px); }
.principle-icon { margin-bottom: 12px; font-size: 32px; }
.principle-card h3 { margin: 0 0 8px; color: #e5e7eb; font-size: 17px; }
.principle-card p { margin: 0; color: #9ca3af; font-size: 13px; line-height: 1.6; }

.pricing-section { padding-top: 96px; padding-bottom: 100px; }
.pricing-eyebrow { text-align: center; }
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  max-width: 1120px;
  margin: 0 auto;
  align-items: stretch;
}
.pricing-card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 520px;
  padding: 30px;
  overflow: hidden;
  border: 1px solid #26303d;
  border-radius: 16px;
  background: linear-gradient(180deg, #161b22 0%, #11161d 100%);
  box-shadow: 0 16px 44px rgba(0, 0, 0, .18);
}
.pricing-card-featured {
  border-color: rgba(110, 231, 183, .58);
  background: linear-gradient(180deg, rgba(24, 48, 52, .88) 0%, #121920 48%, #11161d 100%);
  box-shadow: 0 22px 64px rgba(39, 174, 153, .14), 0 0 0 1px rgba(110, 231, 183, .08);
  transform: translateY(-8px);
}
.pricing-popular {
  position: absolute;
  top: 18px;
  right: -35px;
  width: 140px;
  padding: 6px 0;
  background: linear-gradient(135deg, #6ee7b7, #3b82f6);
  color: #071018;
  font-size: 10px;
  font-weight: 750;
  letter-spacing: .08em;
  text-align: center;
  text-transform: uppercase;
  transform: rotate(38deg);
}
.pricing-card h3 { margin: 0 0 22px; color: #f3f4f6; font-size: 20px; }
.pricing-price { display: flex; align-items: baseline; gap: 9px; min-height: 58px; margin-bottom: 12px; }
.pricing-price strong { color: #f3f4f6; font-size: 38px; line-height: 1; letter-spacing: -.035em; }
.pricing-card-featured .pricing-price strong {
  background: linear-gradient(135deg, #6ee7b7, #60a5fa);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.pricing-price span { color: #6b7280; font-size: 12px; }
.pricing-summary { min-height: 48px; margin: 0 0 22px; color: #9ca3af; font-size: 14px; line-height: 1.65; }
.pricing-features { margin: 0 0 28px; padding: 20px 0 0; border-top: 1px solid rgba(255, 255, 255, .07); list-style: none; }
.pricing-features li { position: relative; padding: 7px 0 7px 24px; color: #c5cdd9; font-size: 13.5px; line-height: 1.5; }
.pricing-features li::before { position: absolute; top: 7px; left: 0; color: #6ee7b7; content: "✓"; font-weight: 750; }
.pricing-features li.pricing-muted { color: #6b7280; }
.pricing-features li.pricing-muted::before { color: #4b5563; content: "—"; }
.pricing-action {
  display: block;
  margin-top: auto;
  padding: 12px 18px;
  border-radius: 8px;
  font-size: 13.5px;
  font-weight: 650;
  text-align: center;
  text-decoration: none;
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.pricing-action:hover { transform: translateY(-1px); }
.pricing-action-primary { background: linear-gradient(135deg, #6ee7b7, #60a5fa); color: #071018; box-shadow: 0 10px 28px rgba(59, 130, 246, .18); }
.pricing-action-secondary { border: 1px solid #374151; background: rgba(10, 14, 20, .35); color: #e5e7eb; }
.pricing-action-secondary:hover { border-color: #6ee7b7; color: #6ee7b7; }
.pricing-note { max-width: 900px; margin: 26px auto 0; color: #667080; font-size: 12px; line-height: 1.65; text-align: center; }

.section-cta { padding-top: 104px; padding-bottom: 104px; background: radial-gradient(ellipse at center, rgba(110, 231, 183, .06), transparent 60%); text-align: center; }
.section-cta .eyebrow { margin-bottom: 12px; }
.cta-title { max-width: 760px; margin: 0 auto 12px; color: #f3f4f6; font-size: 36px; line-height: 1.25; }
.cta-subtitle { margin: 0 auto 32px; color: #9ca3af; font-size: 17px; }
.cta-buttons { justify-content: center; }

.landing-footer { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; padding: 24px 40px; border-top: 1px solid #1f2937; color: #6b7280; font-size: 13px; }
.footer-left { display: flex; align-items: center; gap: 8px; }
.landing-footer a { color: #9ca3af; text-decoration: none; }
.landing-footer a:hover { color: #6ee7b7; }

@media (max-width: 980px) {
  .hero { grid-template-columns: 1fr; gap: 44px; padding: 66px 30px 82px; }
  .hero-text { max-width: 700px; }
  .hero-visual { justify-content: flex-start; }
  .flow { flex-direction: column; max-width: 520px; align-items: stretch; }
  .flow-step { min-width: 0; }
  .flow-arrow { align-self: center; transform: rotate(90deg); }
  .demo-grid, .principles-grid { grid-template-columns: 1fr 1fr; }
  .pricing-grid { grid-template-columns: 1fr; max-width: 560px; }
  .pricing-card { min-height: auto; }
  .pricing-card-featured { transform: none; }
}

@media (max-width: 700px) {
  .landing-nav { padding: 14px 18px; }
  .nav-links { gap: 10px; }
  .nav-links a:not(.nav-cta) { display: none; }
  .nav-cta { padding: 8px 12px; font-size: 12px; }
  .hero { padding: 54px 20px 64px; }
  .hero-title { font-size: 42px; }
  .hero-subtitle { font-size: 15px; }
  .hero-meta { display: grid; gap: 5px; }
  .section { padding: 64px 20px; }
  .section-title { font-size: 30px; }
  .section-subtitle { font-size: 15px; }
  .compare-grid, .demo-grid, .principles-grid, .pricing-grid { grid-template-columns: 1fr; }
  .compare-card, .demo-tile { padding: 24px; }
  .cta-title { font-size: 29px; }
  .landing-footer { padding: 20px; }
}