:root {
  --bg: #0D1117;
  --surface: #161B22;
  --surface-2: #21262D;
  --border: #30363D;
  --fg: #E6EDF3;
  --fg-muted: #8B949E;
  --accent: #00D4FF;
  --accent-dim: rgba(0, 212, 255, 0.12);
  --accent-glow: rgba(0, 212, 255, 0.25);
  --warning: #F0883E;
  --warning-dim: rgba(240, 136, 62, 0.12);
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: 'DM Sans', sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* NAVBAR */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 20px 40px;
  background: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Sora', sans-serif;
  font-weight: 700;
  font-size: 18px;
  color: var(--fg);
  letter-spacing: -0.3px;
}

.nav-tagline {
  font-size: 13px;
  color: var(--fg-muted);
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

/* HERO */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 120px 40px 80px;
  background: var(--bg);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(ellipse, rgba(0, 212, 255, 0.06) 0%, transparent 70%);
  pointer-events: none;
}

.hero-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
  width: 100%;
}

.hero-eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
}

.hero-headline {
  font-family: 'Sora', sans-serif;
  font-size: clamp(40px, 5vw, 64px);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -2px;
  color: var(--fg);
  margin-bottom: 28px;
}

.hero-sub {
  font-size: 18px;
  color: var(--fg-muted);
  line-height: 1.65;
  max-width: 480px;
}

/* TRACE DIAGRAM */
.trace-diagram {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  font-family: 'Sora', sans-serif;
}

.trace-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.trace-label {
  font-size: 11px;
  color: var(--fg-muted);
  letter-spacing: 0.5px;
}

.trace-status {
  font-size: 10px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 20px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.trace-status.active {
  background: var(--accent-dim);
  color: var(--accent);
  border: 1px solid rgba(0, 212, 255, 0.2);
}

.trace-nodes {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.trace-node.root {
  display: flex;
  flex-direction: column;
  margin-bottom: 12px;
}

.trace-branches {
  display: flex;
  gap: 16px;
  padding-left: 24px;
  border-left: 1px solid var(--border);
  margin-left: 8px;
}

.trace-branches .trace-node {
  display: flex;
  flex-direction: column;
}

.node-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 8px var(--accent-glow);
  flex-shrink: 0;
  margin: 6px 0;
}

.node-dot.warning {
  background: var(--warning);
  box-shadow: 0 0 8px rgba(240, 136, 62, 0.4);
}

.node-line {
  width: 1px;
  height: 20px;
  background: var(--border);
  margin-left: 4px;
}

.node-card {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 14px;
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}

.node-card.warning {
  border-color: rgba(240, 136, 62, 0.3);
}

.node-model {
  font-size: 11px;
  color: var(--fg-muted);
  font-family: 'Sora', monospace;
}

.node-latency {
  font-size: 11px;
  color: var(--fg-muted);
}

.node-cost {
  font-size: 11px;
  color: var(--fg);
  font-weight: 600;
}

.node-cost.warning {
  color: var(--warning);
}

.node-flag {
  font-size: 9px;
  padding: 2px 6px;
  border-radius: 4px;
  background: var(--warning-dim);
  color: var(--warning);
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.trace-metrics {
  display: flex;
  gap: 24px;
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

.metric {
  display: flex;
  align-items: baseline;
  gap: 6px;
}

.metric-val {
  font-family: 'Sora', sans-serif;
  font-size: 18px;
  font-weight: 700;
  color: var(--fg);
}

.metric-key {
  font-size: 11px;
  color: var(--fg-muted);
}

.uptime-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #3FB950;
  box-shadow: 0 0 6px rgba(63, 185, 80, 0.5);
}

/* SIGNAL SECTION */
.signal-section {
  padding: 100px 40px;
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.signal-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.signal-eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
}

.signal-headline {
  font-family: 'Sora', sans-serif;
  font-size: clamp(28px, 3vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -1px;
  color: var(--fg);
  margin-bottom: 24px;
}

.signal-body {
  font-size: 16px;
  color: var(--fg-muted);
  line-height: 1.7;
  margin-bottom: 16px;
}

/* PRICING BAR CHART */
.signal-bar-group {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.bar-row {
  display: grid;
  grid-template-columns: 80px 1fr 60px;
  gap: 12px;
  align-items: center;
}

.bar-label {
  font-size: 13px;
  color: var(--fg-muted);
  font-family: 'Sora', sans-serif;
}

.bar-fill {
  height: 28px;
  border-radius: 6px;
  transition: width 0.5s ease;
}

.bar-fill.full { background: linear-gradient(90deg, #6366F1, #8B5CF6); width: 100%; opacity: 0.6; }
.bar-fill.med { background: linear-gradient(90deg, #3B82F6, #60A5FA); width: 55%; opacity: 0.6; }
.bar-fill.target { background: linear-gradient(90deg, var(--accent), #00E5C9); width: 35%; box-shadow: 0 0 12px var(--accent-glow); }
.bar-fill.none { background: var(--surface-2); width: 8%; }

.bar-price {
  font-size: 13px;
  color: var(--fg-muted);
  text-align: right;
}

.bar-row.current .bar-label { color: var(--accent); font-weight: 700; }
.bar-row.current .bar-price { color: var(--accent); font-weight: 700; }

.signal-caption {
  font-size: 12px;
  color: var(--fg-muted);
  margin-top: 16px;
  font-style: italic;
}

/* FEATURES */
.features {
  padding: 100px 40px;
  background: var(--bg);
}

.features-inner {
  max-width: 1200px;
  margin: 0 auto;
}

.section-eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
  text-align: center;
  margin-bottom: 16px;
}

.section-headline {
  font-family: 'Sora', sans-serif;
  font-size: clamp(28px, 3vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -1px;
  color: var(--fg);
  text-align: center;
  margin-bottom: 60px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.feature-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.feature-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--accent-dim);
  border: 1px solid rgba(0, 212, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  margin-bottom: 20px;
}

.feature-card h3 {
  font-family: 'Sora', sans-serif;
  font-size: 17px;
  font-weight: 700;
  color: var(--fg);
  margin-bottom: 10px;
}

.feature-card p {
  font-size: 14px;
  color: var(--fg-muted);
  line-height: 1.65;
}

/* MANIFESTO */
.manifesto {
  padding: 100px 40px;
  background: var(--surface);
  border-top: 1px solid var(--border);
}

.manifesto-inner {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.manifesto-headline {
  font-family: 'Sora', sans-serif;
  font-size: clamp(28px, 3.5vw, 44px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -1.5px;
  color: var(--fg);
  margin-bottom: 32px;
}

.manifesto-body {
  font-size: 17px;
  color: var(--fg-muted);
  line-height: 1.75;
}

.manifesto-body p {
  margin-bottom: 18px;
}

.manifesto-cta {
  font-family: 'Sora', sans-serif;
  font-size: 20px;
  font-weight: 600;
  color: var(--fg);
  margin-top: 28px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

/* CLOSING */
.closing {
  padding: 120px 40px;
  background: var(--bg);
  text-align: center;
  position: relative;
}

.closing::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 400px;
  background: radial-gradient(ellipse, rgba(0, 212, 255, 0.05) 0%, transparent 70%);
  pointer-events: none;
}

.closing-inner {
  position: relative;
  z-index: 1;
}

.closing-headline {
  font-family: 'Sora', sans-serif;
  font-size: clamp(32px, 4.5vw, 56px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -2px;
  color: var(--fg);
  margin-bottom: 20px;
}

.closing-body {
  font-size: 22px;
  color: var(--accent);
  font-family: 'Sora', sans-serif;
  font-weight: 600;
}

/* FOOTER */
.footer {
  padding: 40px;
  border-top: 1px solid var(--border);
  background: var(--surface);
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: 'Sora', sans-serif;
  font-weight: 700;
  font-size: 16px;
  color: var(--fg);
}

.footer-copy {
  font-size: 13px;
  color: var(--fg-muted);
}

/* RESPONSIVE */
@media (max-width: 900px) {
  .hero-inner,
  .signal-inner {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero {
    padding-top: 100px;
  }

  .trace-diagram {
    margin-top: 0;
  }
}

@media (max-width: 600px) {
  .navbar { padding: 16px 20px; }
  .hero { padding: 80px 20px 60px; }
  .signal-section { padding: 60px 20px; }
  .features { padding: 60px 20px; }
  .manifesto { padding: 60px 20px; }
  .closing { padding: 80px 20px; }
  .footer { padding: 32px 20px; }

  .feature-grid {
    grid-template-columns: 1fr;
  }

  .trace-metrics {
    flex-wrap: wrap;
    gap: 16px;
  }

  .trace-branches {
    flex-direction: column;
    padding-left: 12px;
  }

  .nav-tagline { display: none; }
}