/* Positron — Guara Cloud family design system, Positron lane.
   Blue = logs · rose = traces · green = evidence. Everywhere. */

:root {
  --font-display: "Afacad Flux", "Segoe UI", sans-serif;
  --font-body: "Atkinson Hyperlegible", "Segoe UI", sans-serif;
  --font-code: "Recursive Mono", "SFMono-Regular", Consolas, monospace;

  /* Light field */
  --ink: oklch(19% 0.028 265);
  --ink-muted: oklch(40% 0.03 265);
  --surface: oklch(98% 0.008 262);
  --surface-raised: oklch(95.5% 0.014 262);
  --surface-strong: oklch(91% 0.022 262);
  --line: oklch(86% 0.02 262);

  /* Deep field — the chamber */
  --deep: oklch(16% 0.03 268);
  --deep-raised: oklch(21% 0.038 268);
  --deep-strong: oklch(27% 0.045 268);
  --deep-line: oklch(36% 0.05 268);
  --deep-ink: oklch(94% 0.012 262);
  --deep-ink-muted: oklch(76% 0.028 262);

  /* Signal hues */
  --positron: oklch(46% 0.17 262);
  --positron-bright: oklch(72% 0.14 262);
  --positron-soft: oklch(92.5% 0.04 262);
  --trace: oklch(54% 0.17 342);
  --trace-bright: oklch(74% 0.13 342);
  --trace-soft: oklch(93% 0.038 342);
  --verify: oklch(50% 0.115 166);
  --verify-bright: oklch(76% 0.115 166);
  --verify-soft: oklch(92.5% 0.042 166);
  --warn: oklch(55% 0.12 76);
  --warn-bright: oklch(78% 0.11 76);
  --warn-soft: oklch(93.5% 0.045 76);

  --space-2xs: 4px;
  --space-xs: 8px;
  --space-sm: 12px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;
  --space-5xl: clamp(96px, 14vw, 160px);

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);

  --shadow-soft: 0 18px 50px oklch(19% 0.028 265 / 0.09);
  --shadow-deep: 0 24px 70px oklch(10% 0.03 268 / 0.45);

  --measure: 68ch;
  --page-max: 1180px;

  /* z-scale */
  --z-nav: 40;
  --z-skip: 60;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--surface);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  font-kerning: normal;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.12;
  margin: 0 0 var(--space-md);
  text-wrap: balance;
  letter-spacing: -0.015em;
}

h1 { font-size: clamp(2.5rem, 1.4rem + 4.6vw, 4.5rem); font-weight: 700; }
h2 { font-size: clamp(1.8rem, 1.25rem + 2.2vw, 2.9rem); }
h3 { font-size: clamp(1.25rem, 1.1rem + 0.7vw, 1.6rem); }
h4 { font-size: 1.125rem; }

p { margin: 0 0 var(--space-md); max-width: var(--measure); text-wrap: pretty; }
p:last-child { margin-bottom: 0; }

a {
  color: inherit;
  text-decoration-color: color-mix(in oklch, var(--positron), transparent 45%);
  text-underline-offset: 0.18em;
  transition: text-decoration-color 150ms var(--ease-out);
}
a:hover { text-decoration-color: var(--positron); }

code, .mono {
  font-family: var(--font-code);
  font-variant-ligatures: none;
  font-size: 0.92em;
}

::selection { background: var(--positron-soft); }

.skip-link {
  position: absolute;
  top: -48px;
  left: var(--space-md);
  z-index: var(--z-skip);
  padding: var(--space-xs) var(--space-md);
  background: var(--deep);
  color: var(--deep-ink);
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  text-decoration: none;
  transition: top 150ms var(--ease-out);
}
.skip-link:focus-visible { top: 0; }

:focus-visible {
  outline: 2px solid var(--positron);
  outline-offset: 3px;
  border-radius: 2px;
}
.on-deep :focus-visible, .site-header :focus-visible { outline-color: var(--positron-bright); }

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  background: color-mix(in oklch, var(--deep), transparent 8%);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: var(--deep-ink);
  border-bottom: 1px solid transparent;
  transition: border-color 200ms var(--ease-out);
}
.site-header.is-scrolled { border-bottom-color: var(--deep-line); }

.site-header--light {
  background: color-mix(in oklch, var(--surface), transparent 8%);
  color: var(--ink);
}
.site-header--light.is-scrolled { border-bottom-color: var(--line); }

.site-header__inner {
  max-width: var(--page-max);
  margin: 0 auto;
  padding: var(--space-sm) var(--space-lg);
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.35rem;
  letter-spacing: 0.005em;
}
.brand svg { width: 30px; height: 30px; color: var(--positron-bright); }
.site-header--light .brand svg { color: var(--positron); }
.brand__org {
  display: block;
  font-family: var(--font-code);
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--deep-ink-muted);
  line-height: 1;
}
.site-header--light .brand__org { color: var(--ink-muted); }
.brand__stack { display: flex; flex-direction: column; gap: 3px; line-height: 1; }

.site-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: clamp(var(--space-md), 3vw, var(--space-xl));
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.02rem;
}
.site-nav a { text-decoration: none; padding: var(--space-xs) 0; }
.site-nav a:hover { text-decoration: underline; text-decoration-color: var(--positron-bright); text-underline-offset: 0.3em; }
.site-header--light .site-nav a:hover { text-decoration-color: var(--positron); }
.site-nav a[aria-current="page"] {
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-decoration-color: var(--positron-bright);
  text-underline-offset: 0.3em;
}
.site-header--light .site-nav a[aria-current="page"] { text-decoration-color: var(--positron); }

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 0.72em 1.35em;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: transform 130ms var(--ease-out), background-color 130ms var(--ease-out),
              border-color 130ms var(--ease-out), box-shadow 130ms var(--ease-out);
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0) scale(0.98); }

.btn--primary { background: var(--positron); color: oklch(98% 0.008 262); }
.btn--primary:hover { background: oklch(52% 0.17 262); box-shadow: 0 8px 24px oklch(46% 0.17 262 / 0.35); }

.on-deep .btn--primary { background: var(--positron-bright); color: var(--deep); }
.on-deep .btn--primary:hover { background: oklch(78% 0.13 262); box-shadow: 0 8px 28px oklch(72% 0.14 262 / 0.3); }

.btn--ghost { border-color: var(--line); color: inherit; }
.btn--ghost:hover { border-color: var(--positron); }
.on-deep .btn--ghost { border-color: var(--deep-line); }
.on-deep .btn--ghost:hover { border-color: var(--positron-bright); }

/* ---------- Page scaffolding ---------- */

.container {
  max-width: var(--page-max);
  margin: 0 auto;
  padding-inline: var(--space-lg);
}

.section { padding-block: var(--space-5xl); }
.section--tight { padding-block: var(--space-4xl); }

.section-head { max-width: 780px; margin-bottom: clamp(var(--space-xl), 6vw, var(--space-3xl)); }
.section-head .lede { font-size: 1.2rem; color: var(--ink-muted); }

.on-deep {
  background: var(--deep);
  color: var(--deep-ink);
}
.on-deep .section-head .lede { color: var(--deep-ink-muted); }

/* ---------- Hero ---------- */

.hero {
  position: relative;
  overflow: clip;
  display: grid;
}
.hero__chamber,
.hero__fallback {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.hero__fallback { object-fit: cover; opacity: 0.85; }
.js .hero__fallback.is-replaced { display: none; }

.hero__content {
  position: relative;
  max-width: var(--page-max);
  width: 100%;
  margin: 0 auto;
  padding: clamp(96px, 16vh, 180px) var(--space-lg) clamp(80px, 12vh, 150px);
}
.hero__content h1 { max-width: 15ch; margin-bottom: var(--space-lg); }
.hero__lede {
  font-size: clamp(1.15rem, 1rem + 0.7vw, 1.4rem);
  max-width: 52ch;
  color: var(--deep-ink-muted);
  margin-bottom: var(--space-xl);
}
.hero__lede strong { color: var(--deep-ink); font-weight: 400; }
.hero__actions { display: flex; flex-wrap: wrap; gap: var(--space-md); align-items: center; }
.hero__meta {
  margin-top: var(--space-2xl);
  font-family: var(--font-code);
  font-weight: 500;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
  color: var(--deep-ink-muted);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs) var(--space-lg);
}
.hero__meta a { text-decoration-color: color-mix(in oklch, var(--positron-bright), transparent 50%); }
.hero__meta a:hover { text-decoration-color: var(--positron-bright); }

/* ---------- Signal legend (blue=logs, rose=traces) ---------- */

.signal {
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
  font-family: var(--font-code);
  font-weight: 500;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
}
.signal::before {
  content: "";
  width: 9px; height: 9px;
  border-radius: 50%;
  background: currentColor;
}
.signal--logs { color: var(--positron); }
.signal--traces { color: var(--trace); }
.on-deep .signal--logs { color: var(--positron-bright); }
.on-deep .signal--traces { color: var(--trace-bright); }

/* ---------- Split feature (copy + diagram) ---------- */

.split {
  display: grid;
  grid-template-columns: minmax(320px, 5fr) minmax(300px, 6fr);
  gap: clamp(var(--space-xl), 6vw, var(--space-4xl));
  align-items: center;
}
.split--flip { grid-template-columns: minmax(300px, 6fr) minmax(320px, 5fr); }
.split__copy .lede { font-size: 1.15rem; color: var(--ink-muted); }

.panel {
  background: var(--deep);
  color: var(--deep-ink);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-deep);
  padding: clamp(var(--space-md), 3vw, var(--space-xl));
}
.panel svg { display: block; width: 100%; height: auto; }

/* ---------- Pillars: alternating ledger rows, not cards ---------- */

.pillars { display: flex; flex-direction: column; }
.pillar {
  display: grid;
  grid-template-columns: minmax(210px, 340px) 1fr;
  gap: var(--space-md) clamp(var(--space-lg), 5vw, var(--space-4xl));
  padding-block: clamp(var(--space-xl), 4.5vw, var(--space-2xl));
  border-top: 1px solid var(--line);
}
.pillar:last-child { border-bottom: 1px solid var(--line); }
.pillar h3 { margin-bottom: var(--space-2xs); }
.pillar__kicker {
  font-family: var(--font-code);
  font-weight: 500;
  font-size: 0.82rem;
  letter-spacing: 0.05em;
  color: var(--ink-muted);
}
.pillar__body p { max-width: 62ch; }
.pillar__body .fact {
  display: block;
  margin-top: var(--space-sm);
  font-family: var(--font-code);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--positron);
}

/* ---------- Wire in / read out ---------- */

.io {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(var(--space-lg), 4vw, var(--space-3xl));
  align-items: stretch;
}
.io__col { min-width: 0; }
.io__col h3 { display: flex; align-items: baseline; gap: var(--space-sm); }
.io__list { list-style: none; margin: 0; padding: 0; }
.io__list li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-md);
  align-items: baseline;
  padding-block: var(--space-sm);
  border-top: 1px solid var(--deep-line);
}
.io__list li:first-child { border-top: none; }
.io__list .mono { color: var(--positron-bright); white-space: nowrap; font-size: 0.9rem; }
.io__list.io__list--out .mono { color: var(--trace-bright); }
.io__list span:last-child { color: var(--deep-ink-muted); }

/* ---------- CLI block ---------- */

.cli {
  background: var(--deep);
  color: var(--deep-ink);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-deep);
  overflow: hidden;
  font-size: 0.95rem;
}
.cli__bar {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--deep-line);
  font-family: var(--font-code);
  font-size: 0.8rem;
  color: var(--deep-ink-muted);
}
.cli__bar::before {
  content: "";
  width: 10px; height: 10px;
  border-radius: 50%;
  background: var(--verify-bright);
}
.cli pre {
  margin: 0;
  padding: var(--space-lg) var(--space-md) var(--space-lg) var(--space-lg);
  overflow-x: auto;
  font-family: var(--font-code);
  font-weight: 500;
  line-height: 1.8;
}
.cli .c { color: var(--deep-ink-muted); }
.cli .p { color: var(--positron-bright); }

/* ---------- Ops list ---------- */

.ops { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; }
.ops li { padding-block: var(--space-md); border-top: 1px solid var(--line); max-width: 60ch; }
.ops li:last-child { border-bottom: 1px solid var(--line); }
.ops b { font-family: var(--font-display); font-weight: 600; font-size: 1.08rem; display: block; margin-bottom: 2px; }
.ops span { color: var(--ink-muted); }

/* ---------- Footer ---------- */

.site-footer {
  background: var(--deep);
  color: var(--deep-ink);
  padding-block: var(--space-3xl) var(--space-2xl);
  margin-top: var(--space-5xl);
}
.hero + .site-footer, .section:last-of-type + .site-footer { margin-top: 0; }
.site-footer__inner {
  max-width: var(--page-max);
  margin: 0 auto;
  padding-inline: var(--space-lg);
  display: grid;
  grid-template-columns: 1fr auto auto;
  gap: var(--space-2xl) clamp(var(--space-2xl), 8vw, var(--space-4xl));
}
.site-footer .brand { font-size: 1.2rem; }
.site-footer .brand svg { color: var(--positron-bright); }
.site-footer__tag { color: var(--deep-ink-muted); max-width: 34ch; margin-top: var(--space-md); }
.site-footer h4 {
  font-family: var(--font-code);
  font-weight: 500;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--deep-ink-muted);
  margin-bottom: var(--space-sm);
}
.site-footer ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: var(--space-xs); }
.site-footer a { text-decoration-color: transparent; }
.site-footer a:hover { text-decoration-color: var(--positron-bright); }
.site-footer__legal {
  max-width: var(--page-max);
  margin: var(--space-2xl) auto 0;
  padding: var(--space-lg) var(--space-lg) 0;
  border-top: 1px solid var(--deep-line);
  color: var(--deep-ink-muted);
  font-size: 0.92rem;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs) var(--space-lg);
  justify-content: space-between;
}

/* ---------- Reveal system (visible by default; JS enhances) ---------- */

.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 650ms var(--ease-out), transform 650ms var(--ease-out);
  transition-delay: var(--reveal-delay, 0ms);
}
.js [data-reveal].in-view { opacity: 1; transform: none; }

/* ---------- Diagram animation primitives ---------- */

.flow-edge {
  stroke-dasharray: 6 8;
  animation: flow 1.6s linear infinite;
}
@keyframes flow { to { stroke-dashoffset: -14; } }

.pulse-node { animation: pulse 3.2s var(--ease-out) infinite; transform-origin: center; transform-box: fill-box; }
@keyframes pulse {
  0%, 100% { opacity: 0.75; }
  50% { opacity: 1; }
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  .split, .split--flip { grid-template-columns: 1fr; }
  .split--flip .panel { order: -1; }
  .io { grid-template-columns: 1fr; }
  .site-footer__inner { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 640px) {
  .pillar { grid-template-columns: 1fr; gap: var(--space-xs); }
  .site-footer__inner { grid-template-columns: 1fr; gap: var(--space-xl); }
  .brand__org { display: none; }
  .site-nav { font-size: 0.98rem; gap: var(--space-md); }
  .hero__meta { gap: var(--space-xs) var(--space-md); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .flow-edge, .pulse-node { animation: none; }
  .js [data-reveal] { opacity: 1; transform: none; transition: none; }
  .btn, a { transition: none; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}