/* ============================================================
   Talvigen - marketing site stylesheet
   Slate & Teal design system (see .claude/skills/talvigen-design).
   Static site; tokens are inlined here so the folder deploys
   anywhere with no build step.
   ============================================================ */

:root {
  /* Slate neutral ramp (hue 230) */
  --slate-0:   oklch(100% 0 0);
  --slate-25:  oklch(99% 0.003 230);
  --slate-50:  oklch(97% 0.005 230);
  --slate-100: oklch(94% 0.008 230);
  --slate-200: oklch(88% 0.01 230);
  --slate-300: oklch(80% 0.012 230);
  --slate-400: oklch(66% 0.014 230);
  --slate-500: oklch(54% 0.016 230);
  --slate-600: oklch(44% 0.018 230);
  --slate-700: oklch(34% 0.02 230);
  --slate-800: oklch(27% 0.02 230);
  --slate-900: oklch(22% 0.02 230);
  --slate-950: oklch(16% 0.018 235);

  /* Teal accent ramp (hue 195) */
  --teal-50:  oklch(96% 0.02 195);
  --teal-100: oklch(90% 0.04 195);
  --teal-300: oklch(72% 0.09 195);
  --teal-500: oklch(55% 0.1 195);
  --teal-600: oklch(48% 0.1 195);
  --teal-700: oklch(42% 0.095 195);
  --teal-800: oklch(34% 0.075 198);

  /* Semantic aliases */
  --bg-app:         var(--slate-50);
  --bg-subtle:      var(--slate-100);
  --surface:        var(--slate-0);
  --surface-dark:   var(--slate-950);
  --text-primary:   var(--slate-900);
  --text-secondary: var(--slate-600);
  --text-muted:     var(--slate-500);
  --text-on-accent: oklch(99% 0.005 195);
  --text-on-dark:   oklch(94% 0.006 230);
  --text-on-dark-secondary: oklch(75% 0.01 230);
  --text-link:      var(--teal-700);
  --text-link-hover:var(--teal-800);
  --border-subtle:  var(--slate-200);
  --border:         var(--slate-300);
  --accent:         var(--teal-600);
  --accent-hover:   var(--teal-700);
  --accent-active:  var(--teal-800);
  --accent-subtle:  var(--teal-50);
  --accent-ring:    oklch(55% 0.1 195 / 0.35);

  /* Type */
  --font-display: "Space Grotesk", "Segoe UI", system-ui, sans-serif;
  --font-body:    "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --font-mono:    "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --ls-tight:  -0.02em;
  --ls-kicker: 0.12em;

  /* Spacing, radii, motion */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --container: 1120px;
  --pad-x: 56px;
  --ease-standard: cubic-bezier(0.2, 0, 0, 1);
  --dur-fast: 120ms;
  --dur-med: 180ms;
}

/* ---------- Base ---------- */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
[id] { scroll-margin-top: 88px; }
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.5;
  background: var(--surface);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: var(--ls-tight);
  margin: 0;
}
p { margin: 0; }
a { color: var(--text-link); }
a:hover { color: var(--text-link-hover); }
:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px var(--accent-ring);
  border-radius: var(--radius-sm);
}

/* ---------- Kicker motif ---------- */
.kicker {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: var(--ls-kicker);
  text-transform: uppercase;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.kicker::before { content: ""; width: 26px; height: 1.5px; background: var(--accent); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 15px;
  border-radius: var(--radius-md);
  padding: 12px 20px;
  border: 1px solid transparent;
  text-decoration: none;
  cursor: pointer;
  transition: background var(--dur-fast) var(--ease-standard),
              border-color var(--dur-fast) var(--ease-standard),
              color var(--dur-fast) var(--ease-standard);
}
.btn-primary { background: var(--accent); color: var(--text-on-accent); border-color: var(--accent); }
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--text-on-accent); }
.btn-primary:active { background: var(--accent-active); }
.btn-ghost { background: transparent; color: var(--text-primary); border-color: var(--border); }
.btn-ghost:hover { background: var(--bg-subtle); color: var(--text-primary); }
.btn-sm { padding: 9px 16px; font-size: 14px; }

/* ---------- Nav ---------- */
nav.site-nav {
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--pad-x);
  border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  background: oklch(100% 0 0 / 0.85);
  backdrop-filter: blur(8px);
  z-index: 10;
}
.wordmark {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 21px;
  letter-spacing: var(--ls-tight);
  color: var(--text-primary);
  text-decoration: none;
}
.wordmark:hover { color: var(--text-primary); }
.navlinks { display: flex; gap: 32px; font-size: 14.5px; font-weight: 500; }
.navlinks a { color: var(--text-secondary); text-decoration: none; }
.navlinks a:hover, .navlinks a[aria-current="page"] { color: var(--text-primary); }

/* ---------- Hero ---------- */
.hero { padding: 96px var(--pad-x) 80px; max-width: var(--container); margin: 0 auto; }
.hero h1 { font-size: clamp(38px, 6vw, 60px); line-height: 1.05; margin-top: 22px; max-width: 16ch; }
.hero .lede { font-size: 19px; line-height: 1.5; color: var(--text-secondary); max-width: 56ch; margin-top: 24px; }
.hero .cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 36px; }

/* Page hero (subpages) */
.page-hero { padding: 72px var(--pad-x) 56px; max-width: var(--container); margin: 0 auto; }
.page-hero h1 { font-size: clamp(32px, 5vw, 48px); line-height: 1.08; margin-top: 20px; max-width: 22ch; }
.page-hero .lede { font-size: 18px; line-height: 1.55; color: var(--text-secondary); max-width: 58ch; margin-top: 20px; }
.page-hero .cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }

/* ---------- Specialty strip ---------- */
.strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}
.strip .m { padding: 28px 32px; border-right: 1px solid var(--border-subtle); }
.strip .m:first-child { padding-left: var(--pad-x); }
.strip .m:last-child { border-right: none; }
.strip .lab {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: var(--ls-kicker);
  text-transform: uppercase;
  color: var(--text-muted);
}
.strip .val { font-family: var(--font-display); font-weight: 600; font-size: 18px; margin-top: 8px; }

/* ---------- Sections ---------- */
.section { padding: 80px var(--pad-x); max-width: var(--container); margin: 0 auto; }
.section h2 { font-size: clamp(28px, 4vw, 38px); margin: 16px 0 0; max-width: 24ch; }
.section .section-lede { font-size: 16.5px; line-height: 1.55; color: var(--text-secondary); max-width: 60ch; margin-top: 16px; }

/* Cards */
.grid3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 44px; }
.svc {
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  background: var(--surface);
  text-decoration: none;
  color: inherit;
  transition: border-color var(--dur-med) var(--ease-standard);
}
a.svc:hover { border-color: var(--border); color: inherit; }
.svc .ic {
  width: 42px; height: 42px;
  border-radius: var(--radius-md);
  background: var(--accent-subtle);
  display: flex; align-items: center; justify-content: center;
  color: var(--accent-hover);
  margin-bottom: 18px;
}
.svc h3 { font-size: 19px; margin-bottom: 8px; }
.svc p { font-size: 14.5px; line-height: 1.55; color: var(--text-secondary); }
.svc .meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-top: auto;
  padding-top: 18px;
}
.svc .more { font-size: 14px; font-weight: 600; color: var(--text-link); margin-top: 14px; }

/* ---------- Dark band ---------- */
.band { background: var(--surface-dark); color: var(--text-on-dark); }
.band-inner { max-width: var(--container); margin: 0 auto; padding: 80px var(--pad-x); }
.band .kicker { color: var(--teal-300); display: flex; justify-content: center; }
.band .kicker::before { background: var(--teal-300); }
.band h2 { font-size: clamp(28px, 4vw, 36px); color: var(--text-on-dark); margin: 16px auto 44px; max-width: 26ch; text-align: center; }
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.steps.cols3 { grid-template-columns: repeat(3, 1fr); }
.step { border-top: 1.5px solid var(--teal-500); padding-top: 18px; }
.step .n { font-family: var(--font-mono); font-size: 12px; color: var(--teal-300); }
.step h3 { font-size: 19px; margin: 10px 0 8px; color: var(--text-on-dark); }
.step p { font-size: 14.5px; line-height: 1.55; color: var(--text-on-dark-secondary); }

/* ---------- Principles / prose ---------- */
.principles { margin-top: 44px; display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 48px; }
.principle { border-top: 1px solid var(--border-subtle); padding: 22px 0; }
.principle h3 { font-size: 17px; margin-bottom: 6px; }
.principle p { font-size: 14.5px; line-height: 1.55; color: var(--text-secondary); }

.prose { max-width: 640px; }
.prose p { font-size: 16px; line-height: 1.65; color: var(--text-secondary); margin-top: 18px; }
.prose p:first-child { margin-top: 0; }
.prose strong { color: var(--text-primary); font-weight: 600; }
.prose ul { margin: 18px 0 0; padding-left: 20px; color: var(--text-secondary); }
.prose li { font-size: 15.5px; line-height: 1.6; margin-top: 8px; }

/* Checklist (deliverables) */
.checklist { list-style: none; margin: 24px 0 0; padding: 0; max-width: 640px; }
.checklist li {
  display: flex; gap: 12px; align-items: flex-start;
  padding: 14px 0;
  border-top: 1px solid var(--border-subtle);
  font-size: 15.5px; line-height: 1.55; color: var(--text-secondary);
}
.checklist li:last-child { border-bottom: 1px solid var(--border-subtle); }
.checklist svg { flex: none; margin-top: 3px; color: var(--accent); }
.checklist strong { color: var(--text-primary); font-weight: 600; }

/* FAQ */
.faq { max-width: 720px; margin-top: 36px; }
.faq details { border-top: 1px solid var(--border-subtle); }
.faq details:last-child { border-bottom: 1px solid var(--border-subtle); }
.faq summary {
  cursor: pointer;
  list-style: none;
  padding: 18px 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 16.5px;
  letter-spacing: var(--ls-tight);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--font-mono); color: var(--text-muted); font-weight: 400; }
.faq details[open] summary::after { content: "\2212"; }
.faq details p { padding: 0 0 20px; font-size: 15px; line-height: 1.6; color: var(--text-secondary); max-width: 60ch; }

/* ---------- CTA band ---------- */
.cta-band {
  padding: 88px var(--pad-x);
  text-align: center;
  border-top: 1px solid var(--border-subtle);
}
.cta-band .kicker { justify-content: center; }
.cta-band h2 { font-size: clamp(30px, 4.5vw, 42px); margin: 14px auto 0; max-width: 20ch; }
.cta-band p { font-size: 16.5px; color: var(--text-secondary); max-width: 52ch; margin: 18px auto 0; }
.cta-band .cta { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 32px; }

/* ---------- Footer ---------- */
footer.site-footer {
  border-top: 1px solid var(--border-subtle);
  padding: 32px var(--pad-x);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  color: var(--text-muted);
  font-size: 13px;
  font-family: var(--font-mono);
}
footer.site-footer a { color: var(--text-muted); text-decoration: none; }
footer.site-footer a:hover { color: var(--text-primary); }
.footer-links { display: flex; gap: 24px; }

/* ---------- Scroll reveal ---------- */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity 480ms var(--ease-standard), transform 480ms var(--ease-standard); }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  :root { --pad-x: 32px; }
  .grid3, .steps, .steps.cols3 { grid-template-columns: repeat(2, 1fr); }
  .strip { grid-template-columns: repeat(2, 1fr); }
  .strip .m:nth-child(2n) { border-right: none; }
  .strip .m:nth-child(-n+2) { border-bottom: 1px solid var(--border-subtle); }
}
@media (max-width: 640px) {
  :root { --pad-x: 20px; }
  .navlinks { display: none; }
  .hero { padding-top: 64px; padding-bottom: 56px; }
  .section { padding-top: 56px; padding-bottom: 56px; }
  .band-inner { padding-top: 56px; padding-bottom: 56px; }
  .grid3, .steps, .steps.cols3, .principles, .strip { grid-template-columns: 1fr; }
  .strip .m { border-right: none; border-bottom: 1px solid var(--border-subtle); }
  .strip .m:last-child { border-bottom: none; }
}