/* ============================================================
   Cairn — marketing site styles
   Pure CSS, no frameworks, no build step.
   ============================================================ */

:root {
  /* Palette — slate / stone with a teal accent */
  --stone-50:  #f8fafc;
  --stone-100: #f1f5f9;
  --stone-200: #e2e8f0;
  --stone-300: #cbd5e1;
  --stone-400: #94a3b8;
  --stone-500: #64748b;
  --stone-600: #475569;
  --stone-700: #334155;
  --stone-800: #1e293b;
  --stone-900: #0f172a;
  --stone-950: #0a0f1c;

  --accent:        #14b8a6;
  --accent-strong: #0d9488;
  --accent-soft:   rgba(20, 184, 166, 0.12);
  --amber:         #f59e0b;

  /* Semantic (dark-first) */
  --bg:            var(--stone-950);
  --bg-alt:        var(--stone-900);
  --surface:       #111a2e;
  --surface-2:     #16213b;
  --border:        rgba(148, 163, 184, 0.16);
  --text:          var(--stone-100);
  --text-muted:    var(--stone-400);
  --text-dim:      var(--stone-500);

  --radius:    14px;
  --radius-sm: 9px;
  --container: 1120px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
          Arial, "Apple Color Emoji", "Segoe UI Emoji", sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
          "Liberation Mono", monospace;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg:         var(--stone-50);
    --bg-alt:     #ffffff;
    --surface:    #ffffff;
    --surface-2:  var(--stone-100);
    --border:     var(--stone-200);
    --text:       var(--stone-900);
    --text-muted: var(--stone-600);
    --text-dim:   var(--stone-500);
  }
}

/* ---------- Reset / base ---------- */
*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}

h1, h2, h3 { line-height: 1.15; letter-spacing: -0.02em; margin: 0; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

img, svg { display: block; max-width: 100%; }

code { font-family: var(--mono); }

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 24px;
}

.accent { color: var(--accent); }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #04201d;
  padding: 10px 16px;
  border-radius: 0 0 var(--radius-sm) 0;
  z-index: 200;
  font-weight: 600;
}
.skip-link:focus { left: 0; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.98rem;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s var(--ease), background 0.15s var(--ease),
              border-color 0.15s var(--ease), box-shadow 0.15s var(--ease);
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--accent);
  color: #04201d;
  box-shadow: 0 6px 20px -8px rgba(20, 184, 166, 0.7);
}
.btn--primary:hover { background: var(--accent-strong); }

.btn--ghost {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); }

/* ---------- Nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}
.brand:hover { text-decoration: none; }
.brand__mark { width: 28px; height: 28px; }

.nav__links {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav__links a {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.15s var(--ease);
}
.nav__links a:hover { color: var(--text); text-decoration: none; }
.nav__github {
  border: 1px solid var(--border);
  padding: 7px 14px;
  border-radius: var(--radius-sm);
}
.nav__github:hover { border-color: var(--accent); color: var(--accent) !important; }

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  padding: 8px;
  cursor: pointer;
}
.nav__bar {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.2s var(--ease), opacity 0.2s var(--ease);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 84px 0 64px;
  background:
    radial-gradient(60% 80% at 80% -10%, var(--accent-soft), transparent 60%),
    radial-gradient(50% 60% at 0% 110%, rgba(245, 158, 11, 0.08), transparent 60%);
}
.hero__inner {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  align-items: center;
  gap: 48px;
}
.eyebrow {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin: 0 0 16px;
}
.hero__title {
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-weight: 800;
  margin-bottom: 20px;
}
.hero__lead {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: var(--text-muted);
  max-width: 46ch;
  margin: 0 0 30px;
}
.hero__cta { display: flex; gap: 14px; flex-wrap: wrap; }
.hero__meta {
  margin-top: 22px;
  color: var(--text-dim);
  font-size: 0.9rem;
}

/* Stacked-stones art */
.hero__art { display: flex; justify-content: center; }
.cairn-stack {
  display: flex;
  flex-direction: column-reverse;
  align-items: center;
  gap: 14px;
  filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.35));
}
.stone {
  display: block;
  border-radius: 50%;
  background: linear-gradient(180deg, var(--stone-300), var(--stone-500));
  animation: float 6s ease-in-out infinite;
}
.stone--1 { width: 190px; height: 56px; }
.stone--2 { width: 150px; height: 50px; animation-delay: 0.3s; }
.stone--3 { width: 116px; height: 42px; animation-delay: 0.6s;
            background: linear-gradient(180deg, var(--stone-200), var(--stone-400)); }
.stone--4 { width: 78px;  height: 34px; animation-delay: 0.9s;
            background: linear-gradient(180deg, var(--accent), var(--accent-strong)); }

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-6px); }
}

/* ---------- Demo / terminals ---------- */
.demo { padding: 8px 0 56px; }
.demo__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.terminal {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 24px 60px -30px rgba(0, 0, 0, 0.6);
}
.terminal__bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 11px 14px;
  background: var(--surface-2);
  border-bottom: 1px solid var(--border);
}
.dot {
  width: 11px; height: 11px; border-radius: 50%;
  background: var(--stone-600);
}
.dot:nth-child(1) { background: #ff5f57; }
.dot:nth-child(2) { background: #febc2e; }
.dot:nth-child(3) { background: #28c840; }
.terminal__title {
  margin-left: 6px;
  color: var(--text-dim);
  font-size: 0.8rem;
  font-family: var(--mono);
}
.terminal__body {
  margin: 0;
  padding: 18px 18px 20px;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--stone-200);
}
.terminal--plain { position: relative; }
.terminal--plain .terminal__body { background: var(--surface); }

.c-prompt { color: var(--accent); }
.c-muted  { color: var(--text-dim); }
.c-ok     { color: #28c840; }
.c-warn   { color: var(--amber); }
.c-key    { color: #7dd3fc; }

/* Copy buttons */
.copy-btn {
  margin-left: auto;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.15s var(--ease);
}
.copy-btn:hover { border-color: var(--accent); color: var(--accent); }
.copy-btn.is-copied { color: var(--accent); border-color: var(--accent); }
.copy-btn--corner {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 2;
}

/* ---------- Sections ---------- */
.section { padding: 80px 0; }
.section--alt { background: var(--bg-alt); border-block: 1px solid var(--border); }
.section__title {
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  font-weight: 800;
  text-align: center;
}
.section__sub {
  text-align: center;
  color: var(--text-muted);
  max-width: 56ch;
  margin: 14px auto 0;
  font-size: 1.05rem;
}

/* ---------- Feature grid ---------- */
.grid { list-style: none; margin: 0; padding: 0; display: grid; gap: 20px; }
.grid--features {
  grid-template-columns: repeat(3, 1fr);
  margin-top: 48px;
}
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 24px;
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease),
              box-shadow 0.2s var(--ease);
}
.card:hover {
  transform: translateY(-3px);
  border-color: color-mix(in srgb, var(--accent) 50%, var(--border));
  box-shadow: 0 18px 40px -24px rgba(20, 184, 166, 0.5);
}
.card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px; height: 46px;
  border-radius: 12px;
  background: var(--accent-soft);
  font-size: 1.4rem;
  margin-bottom: 16px;
}
.card h3 { font-size: 1.12rem; margin-bottom: 8px; }
.card p { margin: 0; color: var(--text-muted); font-size: 0.96rem; }

/* ---------- Integrations ---------- */
.integrations {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1.2fr;
  gap: 24px;
  margin-top: 48px;
  align-items: start;
}
.integrations__group {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
}
.integrations__label {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 16px;
}
.logos { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 11px 14px;
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  border: 1px solid var(--border);
  font-weight: 500;
  font-size: 0.95rem;
}
.logo__mark { color: var(--accent); font-size: 0.7rem; line-height: 1; }
.logo--sink {
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
  background: var(--accent-soft);
}

/* ---------- Tabs / install ---------- */
.tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
  margin: 44px 0 22px;
}
.tab {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 9px 20px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.92rem;
  cursor: pointer;
  transition: all 0.15s var(--ease);
}
.tab:hover { color: var(--text); border-color: var(--accent); }
.tab.is-active {
  background: var(--accent);
  color: #04201d;
  border-color: var(--accent);
}

.tabpanels { max-width: 760px; margin-inline: auto; }
.tabpanel { display: none; }
.tabpanel.is-active { display: block; }
.tabpanel__hint { color: var(--text-muted); margin: 0 0 14px; font-size: 0.96rem; }
.tabpanel__hint code {
  background: var(--surface-2);
  padding: 1px 6px;
  border-radius: 5px;
  font-size: 0.85em;
}

/* ---------- CTA strip ---------- */
.cta-strip {
  background:
    radial-gradient(80% 140% at 50% 0%, var(--accent-soft), transparent 70%),
    var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 64px 0;
}
.cta-strip__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  flex-wrap: wrap;
}
.cta-strip h2 { font-size: clamp(1.6rem, 3.5vw, 2.1rem); }
.cta-strip p { margin: 8px 0 0; color: var(--text-muted); }
.cta-strip__buttons { display: flex; gap: 14px; flex-wrap: wrap; }

/* ---------- Contact ---------- */
.contact__card {
  max-width: 680px;
  margin: 44px auto 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 28px;
  box-shadow: 0 24px 60px -30px rgba(0, 0, 0, 0.6);
}
.contact__form { display: grid; gap: 18px; }
.contact__row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}
.field { display: grid; gap: 7px; }
.field__label {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text);
}
.field__opt { color: var(--text-dim); font-weight: 500; }
.field__input {
  width: 100%;
  font-family: var(--font);
  font-size: 0.96rem;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 11px 14px;
  transition: border-color 0.15s var(--ease), box-shadow 0.15s var(--ease);
}
.field__input::placeholder { color: var(--text-dim); }
.field__input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.field__input--area { resize: vertical; min-height: 120px; line-height: 1.6; }
.contact__form .btn { justify-self: start; }

.contact__ok {
  display: flex;
  align-items: center;
  gap: 16px;
  max-width: 680px;
  margin: 44px auto 0;
  background: var(--surface);
  border: 1px solid color-mix(in srgb, var(--accent) 45%, var(--border));
  border-radius: var(--radius);
  padding: 26px 28px;
}
.contact__ok-icon {
  flex: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px; height: 46px;
  border-radius: 50%;
  background: var(--accent);
  color: #04201d;
  font-size: 1.3rem;
  font-weight: 700;
}
.contact__ok h3 { font-size: 1.1rem; margin-bottom: 4px; }
.contact__ok p { margin: 0; color: var(--text-muted); font-size: 0.96rem; }

/* ---------- Footer ---------- */
.footer {
  border-top: 1px solid var(--border);
  padding: 40px 0;
  background: var(--bg);
}
.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  text-align: center;
}
.footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-weight: 700;
  font-size: 1.05rem;
}
.footer__meta { margin: 0; color: var(--text-muted); font-size: 0.92rem; }
.footer__copy { margin: 0; color: var(--text-dim); font-size: 0.88rem; }

/* ---------- Pricing ---------- */
.pricing { padding: 64px 0 80px; }
.pricing__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 48px;
  align-items: stretch;
}
.price-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 26px;
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease),
              box-shadow 0.2s var(--ease);
}
.price-card:hover {
  transform: translateY(-3px);
  border-color: color-mix(in srgb, var(--accent) 50%, var(--border));
  box-shadow: 0 18px 40px -24px rgba(20, 184, 166, 0.5);
}
.price-card--featured {
  border-color: color-mix(in srgb, var(--accent) 55%, var(--border));
  box-shadow: 0 24px 60px -30px rgba(20, 184, 166, 0.55);
}
.price-card__badge {
  align-self: flex-start;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #04201d;
  background: var(--accent);
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 14px;
}
.price-card__name { font-size: 1.25rem; margin-bottom: 6px; }
.price-card__tagline { color: var(--text-muted); font-size: 0.95rem; margin: 0 0 20px; }
.price-card__price {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin-bottom: 4px;
}
.price-card__amount { font-size: 2.4rem; font-weight: 800; letter-spacing: -0.02em; }
.price-card__period { color: var(--text-muted); font-size: 0.92rem; }
.price-card__note { color: var(--text-dim); font-size: 0.86rem; margin: 0 0 22px; }
.price-card__features {
  list-style: none;
  margin: 0 0 26px;
  padding: 0;
  display: grid;
  gap: 11px;
}
.price-card__features li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  color: var(--text-muted);
  font-size: 0.94rem;
}
.price-card__features li::before {
  content: "◆";
  color: var(--accent);
  font-weight: 700;
  flex: none;
}
.price-card .btn { margin-top: auto; width: 100%; }
.pricing__free {
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 40px;
}
.pricing__foot {
  text-align: center;
  color: var(--text-dim);
  font-size: 0.92rem;
  margin-top: 36px;
}
.pricing .docs__block { max-width: 760px; margin: 56px auto 0; }

/* ---------- Docs ---------- */
.docs { padding: 56px 0 80px; }
.docs__layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 48px;
  align-items: start;
  margin-top: 40px;
}
.docs__nav {
  position: sticky;
  top: 88px;
  display: grid;
  gap: 4px;
}
.docs__nav-label {
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin: 0 0 10px;
}
.docs__nav a {
  color: var(--text-muted);
  font-size: 0.94rem;
  padding: 7px 10px;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
}
.docs__nav a:hover {
  color: var(--text);
  text-decoration: none;
  background: var(--surface);
  border-left-color: var(--accent);
}
.docs__main { min-width: 0; }
.docs__block { margin-bottom: 56px; scroll-margin-top: 88px; }
.docs__block > h2 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  margin-bottom: 8px;
}
.docs__lead { color: var(--text-muted); font-size: 1.02rem; margin: 0 0 24px; max-width: 62ch; }
.docs__step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 24px;
  margin-bottom: 16px;
}
.docs__step h3 { font-size: 1.08rem; margin-bottom: 8px; }
.docs__step p { margin: 0; color: var(--text-muted); font-size: 0.96rem; }
.docs__step p + p { margin-top: 10px; }
.docs__step code {
  background: var(--surface-2);
  padding: 1px 6px;
  border-radius: 5px;
  font-size: 0.85em;
}
.faq {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  overflow: hidden;
}
.faq__item { border-bottom: 1px solid var(--border); }
.faq__item:last-child { border-bottom: 0; }
.faq__item > summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 22px;
  font-weight: 600;
  font-size: 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.faq__item > summary::-webkit-details-marker { display: none; }
.faq__item > summary::after {
  content: "+";
  color: var(--accent);
  font-size: 1.3rem;
  font-weight: 400;
  flex: none;
  transition: transform 0.2s var(--ease);
}
.faq__item[open] > summary::after { transform: rotate(45deg); }
.faq__item > summary:hover { color: var(--accent); }
.faq__answer { padding: 0 22px 20px; color: var(--text-muted); font-size: 0.96rem; }
.faq__answer p { margin: 0; }
.support-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 26px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.support-card h3 { font-size: 1.15rem; margin-bottom: 6px; }
.support-card p { margin: 0; color: var(--text-muted); font-size: 0.96rem; max-width: 48ch; }

/* ---------- Responsive ---------- */
@media (max-width: 880px) {
  .pricing__grid { grid-template-columns: 1fr; }
  .docs__layout { grid-template-columns: 1fr; gap: 24px; }
  .docs__nav { position: static; }
}
@media (max-width: 880px) {
  .nav__toggle { display: flex; }
  .nav__links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 8px 24px 18px;
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.18s var(--ease), transform 0.18s var(--ease);
  }
  .nav__links.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .nav__links a { padding: 12px 4px; border-bottom: 1px solid var(--border); }
  .nav__github { text-align: center; margin-top: 10px; border-bottom: 0 !important; }

  .hero__inner { grid-template-columns: 1fr; }
  .hero__art { order: -1; }
  .demo__grid { grid-template-columns: 1fr; }
  .contact__row { grid-template-columns: 1fr; }
  .grid--features { grid-template-columns: 1fr 1fr; }
  .integrations { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .hero { padding: 56px 0 44px; }
  .section { padding: 60px 0; }
  .grid--features { grid-template-columns: 1fr; }
  .cta-strip__inner { flex-direction: column; align-items: flex-start; }
  .stone--1 { width: 150px; }
  .stone--2 { width: 120px; }
  .stone--3 { width: 92px; }
  .stone--4 { width: 64px; }
}