:root {
  --nn-ink-950: #0a0a0a;
  --nn-ink-800: #1f1f1f;
  --nn-slate-700: #3f3f46;
  --nn-muted-500: #71717a;
  --nn-line-300: #d4d4d8;
  --nn-surface-100: #f5f5f5;
  --nn-paper-0: #ffffff;
  --nn-space-xs: 0.5rem;
  --nn-space-sm: 0.75rem;
  --nn-space-md: 1rem;
  --nn-space-lg: 1.5rem;
  --nn-space-xl: 2rem;
  --nn-space-2xl: 2.5rem;
  --page-max: 1180px;
  --font-sans: Inter, Arial, Helvetica, sans-serif;
  --font-mono: "Fira Mono", SFMono-Regular, Consolas, monospace;
}

* { box-sizing: border-box; border-radius: 0; box-shadow: none; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--nn-ink-800);
  background: var(--nn-paper-0);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.48;
}
body::selection { background: var(--nn-ink-950); color: var(--nn-paper-0); }
a { color: inherit; text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 0.18em; }
button, input, textarea, select { font: inherit; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--nn-space-md);
  width: min(var(--page-max), calc(100% - 2rem));
  margin: 0 auto;
  padding: var(--nn-space-md) 0;
  background: color-mix(in srgb, var(--nn-paper-0) 94%, transparent);
  border-bottom: 1px solid var(--nn-line-300);
}
.brand { display: inline-flex; align-items: center; gap: var(--nn-space-sm); }
.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--nn-ink-950);
  color: var(--nn-ink-950);
  background: var(--nn-paper-0);
  font-weight: 700;
  letter-spacing: -0.04em;
}
.brand-copy { display: grid; gap: 1px; }
.brand-copy strong { font-size: 15px; color: var(--nn-ink-950); }
.brand-copy small { color: var(--nn-muted-500); font-size: 11px; font-weight: 500; }
.site-nav { display: flex; align-items: center; gap: var(--nn-space-sm); color: var(--nn-slate-700); font-size: 12px; font-weight: 600; }
.site-nav a { padding: 0.35rem 0.5rem; border: 1px solid transparent; }
.site-nav a:hover { border-color: var(--nn-line-300); text-decoration: none; }

.section-pad { width: min(var(--page-max), calc(100% - 2rem)); margin: 0 auto; padding: 76px 0; }
.section { border-top: 1px solid var(--nn-line-300); }
.surface { width: 100%; max-width: none; padding-left: max(1rem, calc((100vw - var(--page-max)) / 2)); padding-right: max(1rem, calc((100vw - var(--page-max)) / 2)); background: var(--nn-surface-100); }

.hero { display: grid; grid-template-columns: minmax(0, 1.12fr) minmax(320px, 0.88fr); gap: var(--nn-space-xl); align-items: center; min-height: 650px; }
.hero-copy { display: flex; flex-direction: column; justify-content: center; padding: var(--nn-space-xl) 0; }
.eyebrow { margin: 0 0 var(--nn-space-md); color: var(--nn-muted-500); text-transform: uppercase; letter-spacing: 0.14em; font-size: 11px; font-weight: 700; }
h1, h2, h3, p { margin-top: 0; }
h1 { max-width: 900px; margin-bottom: var(--nn-space-lg); color: var(--nn-ink-950); font-size: clamp(3rem, 8vw, 6.8rem); line-height: 0.9; letter-spacing: -0.075em; }
h2 { margin-bottom: var(--nn-space-sm); color: var(--nn-ink-950); font-size: clamp(2rem, 4vw, 3.6rem); line-height: 0.98; letter-spacing: -0.055em; }
h3 { margin-bottom: var(--nn-space-sm); color: var(--nn-ink-800); font-size: 18px; line-height: 1.2; letter-spacing: -0.035em; }
.hero-text, .section-head p, .card p, .lane p, .path p, .signal p, .faq-list p, .final-cta p, .state-output p:not(.panel-label) { color: var(--nn-slate-700); }
.hero-text { max-width: 760px; font-size: 18px; line-height: 1.66; }
.actions { display: flex; flex-wrap: wrap; gap: var(--nn-space-sm); margin-top: var(--nn-space-lg); }
.centered { justify-content: center; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 var(--nn-space-md);
  border: 1px solid var(--nn-ink-950);
  font-weight: 700;
  text-decoration: none;
}
.button:hover { text-decoration: none; background: var(--nn-surface-100); }
.button.primary { color: var(--nn-paper-0); background: var(--nn-ink-950); }
.button.primary:hover { color: var(--nn-paper-0); background: var(--nn-ink-800); }
.button.secondary { color: var(--nn-ink-950); background: var(--nn-paper-0); }

.hero-panel, .card, .lane, .path, .signal, .state-output, .faq-list details, .prompt-box {
  border: 1px solid var(--nn-line-300);
  background: var(--nn-paper-0);
}
.hero-panel { align-self: center; padding: var(--nn-space-lg); }
.panel-label { margin-bottom: var(--nn-space-md); color: var(--nn-muted-500); text-transform: uppercase; letter-spacing: 0.12em; font-size: 11px; font-weight: 700; }
.route-list { display: grid; gap: 0; margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--nn-line-300); }
.route-list li { display: grid; grid-template-columns: 42px 1fr; gap: var(--nn-space-md); padding: var(--nn-space-md) 0; border-bottom: 1px solid var(--nn-line-300); }
.route-list span { color: var(--nn-muted-500); font-family: var(--font-mono); font-size: 12px; }
.route-list strong { display: block; color: var(--nn-ink-950); }
.route-list small { display: block; margin-top: 2px; color: var(--nn-muted-500); line-height: 1.4; }

.section-head { max-width: 880px; margin-bottom: var(--nn-space-xl); }
.section-head.compact { max-width: 760px; }
.three-grid, .lane-grid, .signal-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--nn-space-md); }
.card, .lane, .path, .signal { padding: var(--nn-space-lg); }
.card-index, .path span, .signal span { display: block; margin-bottom: var(--nn-space-xl); color: var(--nn-muted-500); font-family: var(--font-mono); font-size: 12px; text-transform: uppercase; letter-spacing: 0.08em; }

.discovery-router { display: grid; grid-template-columns: 0.8fr 1.2fr; gap: var(--nn-space-md); align-items: stretch; }
.state-buttons { display: grid; border: 1px solid var(--nn-line-300); align-content: start; background: var(--nn-paper-0); }
.state-button {
  width: 100%;
  min-height: 62px;
  border: 0;
  border-bottom: 1px solid var(--nn-line-300);
  background: var(--nn-paper-0);
  color: var(--nn-ink-800);
  text-align: left;
  padding: 0 var(--nn-space-md);
  font-weight: 700;
  cursor: pointer;
}
.state-button:last-child { border-bottom: 0; }
.state-button.active, .state-button:hover { background: var(--nn-surface-100); color: var(--nn-ink-950); }
.state-output { padding: var(--nn-space-lg); min-height: 360px; display: flex; flex-direction: column; align-items: flex-start; justify-content: center; }
.state-output p:not(.panel-label) { max-width: 680px; font-size: 16px; line-height: 1.68; }
.prompt-box { width: 100%; max-width: 680px; margin: var(--nn-space-md) 0 0; padding: var(--nn-space-md); background: var(--nn-surface-100); }
.prompt-box strong { display: block; margin-bottom: var(--nn-space-xs); color: var(--nn-ink-950); }
.prompt-box span { color: var(--nn-slate-700); }

.path-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--nn-space-md); }
.principle-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--nn-space-md); }
.principle-list p { margin: 0; padding: var(--nn-space-md); border: 1px solid var(--nn-line-300); background: var(--nn-paper-0); color: var(--nn-slate-700); }
.principle-list strong { color: var(--nn-ink-950); }
.faq-list { display: grid; gap: var(--nn-space-sm); }
.faq-list details { padding: var(--nn-space-md); }
.faq-list summary { cursor: pointer; color: var(--nn-ink-950); font-weight: 700; }
.faq-list p { margin: var(--nn-space-sm) 0 0; max-width: 820px; }
.final-cta { text-align: center; border-top: 1px solid var(--nn-line-300); }
.final-cta h2 { max-width: 900px; margin-left: auto; margin-right: auto; }
.site-footer { display: flex; align-items: center; justify-content: space-between; gap: var(--nn-space-md); width: min(var(--page-max), calc(100% - 2rem)); margin: 0 auto; padding: var(--nn-space-xl) 0; color: var(--nn-muted-500); border-top: 1px solid var(--nn-line-300); font-size: 12px; }
.site-footer p { margin: 0; }

:focus-visible { outline: 2px solid var(--nn-ink-950); outline-offset: 3px; }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0ms !important; transition-duration: 0ms !important; scroll-behavior: auto !important; }
}

@media (max-width: 960px) {
  .site-header { align-items: flex-start; flex-direction: column; }
  .site-nav { flex-wrap: wrap; }
  .hero, .discovery-router { grid-template-columns: 1fr; min-height: auto; }
  .three-grid, .lane-grid, .signal-grid, .path-grid, .principle-list { grid-template-columns: 1fr; }
  h1 { font-size: clamp(3.1rem, 15vw, 5.2rem); }
}