/* ============================================================
   mutter — landing styles
   Brand tokens v1.0 — frozen, see /docs/BRAND.md
   ============================================================ */

/* ---- Color tokens (light = default) ---- */
:root {
  --mutter-bg-primary: #F7EFE2;
  --mutter-bg-secondary: #EFE4D0;
  --mutter-bg-elevated: #FBF6EC;
  --mutter-text-primary: #1B2A4E;
  --mutter-text-secondary: #3A4D7D;
  --mutter-text-tertiary: #5B6E9D;
  --mutter-text-on-accent: #1B2A4E;
  --mutter-accent-default: #B89763;
  --mutter-accent-pressed: #9B7D43;
  --mutter-accent-disabled: #E3D4B8;
  --mutter-bubble-own: #E8C99B;
  --mutter-bubble-peer: #EFE4D0;
  --mutter-bubble-text-own: #1B2A4E;
  --mutter-bubble-text-peer: #1B2A4E;
  --mutter-surface-card: #FBF6EC;
  --mutter-surface-sheet: #F7EFE2;
  --mutter-separator: #E3D4B8;
  --mutter-status-success: #6B8E4E;
  --mutter-status-warning: #C68A2E;
  --mutter-status-error: #B4513A;
  --mutter-status-info: #5B7BA8;
  --mutter-link: #9B7D43;
  --mutter-focus-ring: #B89763;
}

@media (prefers-color-scheme: dark) {
  :root {
    --mutter-bg-primary: #1B2A4E;
    --mutter-bg-secondary: #152340;
    --mutter-bg-elevated: #293B66;
    --mutter-text-primary: #FBF6EC;
    --mutter-text-secondary: #B3BDD4;
    --mutter-text-tertiary: #8694B8;
    --mutter-text-on-accent: #1B2A4E;
    --mutter-accent-default: #E8C99B;
    --mutter-accent-pressed: #D4B17F;
    --mutter-accent-disabled: #3A4D7D;
    --mutter-bubble-own: #EFD7B2;
    --mutter-bubble-peer: #293B66;
    --mutter-bubble-text-own: #1B2A4E;
    --mutter-bubble-text-peer: #FBF6EC;
    --mutter-surface-card: #293B66;
    --mutter-surface-sheet: #0F1A33;
    --mutter-separator: #3A4D7D;
    --mutter-status-success: #A3C081;
    --mutter-status-warning: #C68A2E;
    --mutter-status-error: #D98A75;
    --mutter-status-info: #B3BDD4;
    --mutter-link: #E8C99B;
    --mutter-focus-ring: #E8C99B;
  }
}

/* ---- Extra brand-derived tokens (gradient anchors for hero) ---- */
:root {
  --mutter-navy-900: #0F1A33;
  --mutter-navy-700: #1B2A4E;
  --mutter-navy-600: #293B66;
  --mutter-cream-100: #F7EFE2;
  --mutter-cream-200: #EFE4D0;
}

/* ---- Typography tokens (BRAND.md §6) ---- */
:root {
  --font-sans: ui-sans-serif, system-ui, -apple-system, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  --font-display: ui-sans-serif, system-ui, -apple-system, "SF Pro Display", "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  /* point → rem: 17pt ≈ 1.0625rem (1pt = 1px = 0.0625rem at 16px root).
     Sizes use clamp() for fluid responsive scaling 360px → 1280px. */
  --size-display:  clamp(2.0rem, 1.4rem + 2.5vw, 2.75rem);   /* 32 → 44 */
  --size-title:    clamp(1.625rem, 1.25rem + 1.6vw, 2.125rem); /* 26 → 34 */
  --size-headline: clamp(1.25rem, 1.1rem + 0.6vw, 1.5rem);   /* 20 → 24 */
  --size-body:     1.0625rem; /* 17pt */
  --size-callout:  1rem;      /* 16pt */
  --size-subhead:  0.9375rem; /* 15pt */
  --size-footnote: 0.8125rem; /* 13pt */
  --size-caption:  0.75rem;   /* 12pt */

  --leading-display:  1.2;
  --leading-headline: 1.25;
  --leading-body:     1.55;

  --weight-regular:  400;
  --weight-medium:   500;
  --weight-semibold: 600;
  --weight-bold:     700;
}

/* ---- Spacing (BRAND.md §7, 4pt grid) ---- */
:root {
  --space-0: 0;
  --space-1: 0.25rem;  /* 4pt */
  --space-2: 0.5rem;   /* 8pt */
  --space-3: 0.75rem;  /* 12pt */
  --space-4: 1rem;     /* 16pt */
  --space-5: 1.25rem;  /* 20pt */
  --space-6: 1.5rem;   /* 24pt */
  --space-8: 2rem;     /* 32pt */
  --space-10: 2.5rem;  /* 40pt */
  --space-12: 3rem;    /* 48pt */
  --space-16: 4rem;    /* 64pt */
  --space-20: 5rem;    /* 80pt */
}

/* ---- Radius ---- */
:root {
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  --radius-full: 9999px;
}

/* ---- Elevation (light theme only — dark uses surface shifts) ---- */
:root {
  --elevation-1: 0 1px 2px rgba(27, 42, 78, 0.06), 0 1px 1px rgba(27, 42, 78, 0.04);
  --elevation-2: 0 4px 8px rgba(27, 42, 78, 0.08), 0 2px 4px rgba(27, 42, 78, 0.05);
  --elevation-3: 0 12px 24px rgba(27, 42, 78, 0.12), 0 4px 8px rgba(27, 42, 78, 0.06);
}

@media (prefers-color-scheme: dark) {
  :root {
    --elevation-1: none;
    --elevation-2: none;
    --elevation-3: none;
  }
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--size-body);
  line-height: var(--leading-body);
  color: var(--mutter-text-primary);
  background-color: var(--mutter-bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--mutter-link);
  text-decoration: underline;
  text-underline-offset: 0.18em;
}
a:hover { color: var(--mutter-accent-pressed); }

:focus-visible {
  outline: 2px solid var(--mutter-focus-ring);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

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

/* ============================================================
   Layout primitives
   ============================================================ */
.container {
  width: 100%;
  max-width: 72rem; /* 1152px */
  margin-inline: auto;
  padding-inline: var(--space-4);
}

@media (min-width: 768px) {
  .container { padding-inline: var(--space-6); }
}

main > section {
  padding-block: var(--space-16);
}

@media (min-width: 768px) {
  main > section { padding-block: var(--space-20); }
}

/* ============================================================
   Hero (single gradient zone per BRAND §10 rule 5)
   ============================================================ */
.hero {
  position: relative;
  padding-block: var(--space-16) var(--space-16);
  background: linear-gradient(180deg, var(--mutter-navy-900) 0%, var(--mutter-navy-700) 100%);
  color: #FBF6EC;
  isolation: isolate;
}

@media (prefers-color-scheme: light) {
  .hero {
    background: linear-gradient(180deg, var(--mutter-cream-100) 0%, var(--mutter-cream-200) 100%);
    color: var(--mutter-text-primary);
  }
}

@media (min-width: 768px) {
  .hero { padding-block: var(--space-20); }
}

.hero__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: var(--space-6);
}

.hero__icon {
  width: clamp(160px, 28vw, 224px);
  height: auto;
  border-radius: var(--radius-xl);
}

.hero__wordmark {
  font-family: var(--font-display);
  font-weight: var(--weight-medium);
  font-size: var(--size-display);
  line-height: var(--leading-display);
  letter-spacing: 0.025em;
  color: var(--mutter-accent-default);
  margin: 0;
}

@media (prefers-color-scheme: light) {
  /* Gold on cream fails contrast (BRAND §4) — use navy for wordmark on light. */
  .hero__wordmark { color: var(--mutter-text-primary); }
}

.hero__subhead {
  font-size: var(--size-headline);
  font-weight: var(--weight-regular);
  line-height: var(--leading-headline);
  max-width: 36ch;
  margin: 0;
  color: inherit;
  opacity: 0.92;
}

.hero__cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: var(--space-3) var(--space-6);
  font-family: inherit;
  font-size: var(--size-callout);
  font-weight: var(--weight-medium);
  line-height: 1;
  color: var(--mutter-text-on-accent);
  background-color: var(--mutter-accent-default);
  border: 0;
  border-radius: var(--radius-full);
  text-decoration: none;
  transition: background-color 120ms ease;
  margin-top: var(--space-2);
}

.hero__cta:hover { background-color: var(--mutter-accent-pressed); color: var(--mutter-text-on-accent); }

/* ============================================================
   Section headings
   ============================================================ */
.section__title {
  font-family: var(--font-display);
  font-size: var(--size-title);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-headline);
  letter-spacing: -0.01em;
  margin: 0 0 var(--space-6) 0;
  color: var(--mutter-text-primary);
}

.section__lede {
  font-size: var(--size-body);
  color: var(--mutter-text-secondary);
  max-width: 60ch;
  margin: 0 0 var(--space-8) 0;
}

/* ============================================================
   Why mutter — card grid
   ============================================================ */
.cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
}

@media (min-width: 768px) {
  .cards { grid-template-columns: repeat(2, 1fr); gap: var(--space-5); }
}

@media (min-width: 1100px) {
  .cards { grid-template-columns: repeat(4, 1fr); }
}

.card {
  background-color: var(--mutter-surface-card);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--elevation-1);
}

.card__title {
  font-size: var(--size-headline);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-headline);
  margin: 0 0 var(--space-2) 0;
  color: var(--mutter-text-primary);
}

.card__body {
  margin: 0;
  font-size: var(--size-subhead);
  color: var(--mutter-text-secondary);
  line-height: 1.5;
}

/* ============================================================
   How it works — ordered steps
   ============================================================ */
.steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
  counter-reset: step;
  list-style: none;
  margin: 0;
  padding: 0;
}

@media (min-width: 900px) {
  .steps { grid-template-columns: repeat(3, 1fr); gap: var(--space-6); }
}

.step {
  position: relative;
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  background-color: var(--mutter-bg-elevated);
  box-shadow: var(--elevation-1);
}

.step__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: var(--radius-full);
  background-color: var(--mutter-accent-default);
  color: var(--mutter-text-on-accent);
  font-family: var(--font-mono);
  font-weight: var(--weight-semibold);
  font-size: var(--size-callout);
  margin-bottom: var(--space-3);
}

.step__title {
  font-size: var(--size-headline);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-headline);
  margin: 0 0 var(--space-2) 0;
  color: var(--mutter-text-primary);
}

.step__body {
  margin: 0;
  font-size: var(--size-subhead);
  color: var(--mutter-text-secondary);
  line-height: 1.5;
}

/* ============================================================
   What we don't do — em-dash list
   ============================================================ */
.no-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-3);
}

@media (min-width: 768px) {
  .no-list { grid-template-columns: repeat(2, 1fr); gap: var(--space-3) var(--space-8); }
}

.no-list li {
  position: relative;
  padding-left: var(--space-6);
  font-size: var(--size-body);
  color: var(--mutter-text-primary);
}

.no-list li::before {
  content: "—";
  position: absolute;
  left: 0;
  top: 0;
  color: var(--mutter-accent-default);
  font-weight: var(--weight-semibold);
}

/* ============================================================
   Open & auditable
   ============================================================ */
.audit {
  background-color: var(--mutter-bg-secondary);
}

.audit__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
  align-items: start;
}

@media (min-width: 900px) {
  .audit__inner { grid-template-columns: 1.4fr 1fr; gap: var(--space-12); }
}

.audit__body p {
  margin: 0 0 var(--space-4) 0;
  color: var(--mutter-text-secondary);
}

.audit__body p:last-child { margin-bottom: 0; }

.audit__repo {
  font-family: var(--font-mono);
  font-size: var(--size-subhead);
  background-color: var(--mutter-surface-card);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  box-shadow: var(--elevation-1);
  word-break: break-all;
}

/* ============================================================
   Status block
   ============================================================ */
.status {
  background-color: var(--mutter-bg-primary);
}

.status__card {
  border-radius: var(--radius-xl);
  background-color: var(--mutter-surface-card);
  padding: var(--space-8);
  box-shadow: var(--elevation-2);
  display: grid;
  gap: var(--space-3);
}

.status__phase {
  font-family: var(--font-mono);
  font-size: var(--size-footnote);
  color: var(--mutter-accent-default);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 0;
}

@media (prefers-color-scheme: light) {
  .status__phase { color: var(--mutter-accent-pressed); }
}

.status__text {
  font-size: var(--size-body);
  color: var(--mutter-text-primary);
  margin: 0;
  max-width: 56ch;
}

.status__meta {
  font-size: var(--size-footnote);
  color: var(--mutter-text-tertiary);
  margin: 0;
  font-variant-numeric: tabular-nums;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--mutter-separator);
  padding-block: var(--space-8);
  color: var(--mutter-text-secondary);
  font-size: var(--size-footnote);
}

.site-footer__grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  align-items: center;
  justify-content: center;
  text-align: center;
}

.site-footer__grid > span,
.site-footer__grid > a {
  display: inline-block;
  white-space: nowrap;
}

.site-footer a { color: var(--mutter-link); }

.site-footer .dot {
  color: var(--mutter-text-tertiary);
  user-select: none;
}

/* ============================================================
   Utilities
   ============================================================ */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}