/* ============================================================
   MONDIUM — Global Narratives Landing Page
   styles.css
   ============================================================ */

/* ── 1. CSS Custom Properties ──────────────────────────────── */

:root {
  /* Color palette */
  --color-bg:          #0a0e13;
  --color-surface:     #111820;
  --color-border:      #1e2d3d;
  --color-text:        #e8edf2;
  --color-text-muted:  #8899aa;
  --color-accent:      #00bcd4;
  --color-accent-dim:  rgba(0, 188, 212, 0.10);

  /* Typography */
  --font-sans: 'IBM Plex Sans', 'Courier New', sans-serif;
  --font-mono: 'IBM Plex Mono', 'Courier New', monospace;

  /* Spacing scale */
  --space-xs:   4px;
  --space-sm:   8px;
  --space-md:  16px;
  --space-lg:  32px;
  --space-xl:  64px;
  --space-2xl: 96px;

  /* Layout */
  --header-height: 60px;
  --max-width:    1100px;
  --gutter:        32px;

  /* Motion */
  --ease-out-expo: cubic-bezier(0.19, 1, 0.22, 1);
  --duration-fast: 180ms;
  --duration-base: 350ms;
}


/* ── 2. Reset / Base ─────────────────────────────────────────── */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
  background-color: var(--color-bg);
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  color: var(--color-accent);
  background: var(--color-accent-dim);
  padding: 1px 5px;
  border-radius: 2px;
}


/* ── 3. Layout Utilities ──────────────────────────────────────── */

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.section-pad {
  padding-top: var(--space-2xl);
  padding-bottom: var(--space-2xl);
}


/* ── 4. Header ───────────────────────────────────────────────── */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 100;
  background: rgba(10, 14, 19, 0.88);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-header__logo {
  height: 28px;
  width: auto;
}

.site-header__cta {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  border: 1px solid var(--color-accent);
  padding: 8px 20px;
  transition:
    background var(--duration-fast) ease,
    color var(--duration-fast) ease;
}

.site-header__cta:hover {
  background: var(--color-accent);
  color: var(--color-bg);
}


/* ── 5. Buttons ──────────────────────────────────────────────── */

.btn-primary {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  padding: 14px 32px;
  background: var(--color-accent);
  color: var(--color-bg);
  border: 1px solid var(--color-accent);
  transition:
    background var(--duration-fast) ease,
    color var(--duration-fast) ease,
    box-shadow var(--duration-fast) ease;
  cursor: pointer;
}

.btn-primary:hover {
  background: transparent;
  color: var(--color-accent);
  box-shadow: 0 0 28px rgba(0, 188, 212, 0.22);
}

.btn-ghost {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  padding: 14px 32px;
  background: transparent;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  transition:
    color var(--duration-fast) ease,
    border-color var(--duration-fast) ease;
  cursor: pointer;
}

.btn-ghost:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}


/* ── 6. Hero Section ─────────────────────────────────────────── */

.hero {
  min-height: 100vh;
  padding-top: calc(var(--header-height) + var(--space-xl));
  padding-bottom: var(--space-2xl);
  display: flex;
  align-items: center;
}

.hero .container {
  display: grid;
  grid-template-columns: 60fr 40fr;
  gap: 56px;
  align-items: center;
}

.hero__eyebrow {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 20px;
}

.hero__title {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(2rem, 3.5vw, 3.1rem);
  line-height: 1.18;
  letter-spacing: -0.015em;
  color: var(--color-text);
  margin-bottom: 24px;
}

.hero__title strong {
  font-weight: 600;
  color: #ffffff;
}

.hero__subhead {
  font-size: 1rem;
  color: var(--color-text-muted);
  max-width: 500px;
  line-height: 1.8;
  margin-bottom: var(--space-lg);
}

.hero__ctas {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  align-items: center;
}


/* ── 7. CIE Annotator Panel ──────────────────────────────────── */

.cie-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-accent);
  border-radius: 3px;
  overflow: visible;
}

.cie-panel__header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 11px 16px;
  border-bottom: 1px solid var(--color-border);
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--color-text-muted);
  letter-spacing: 0.10em;
}

.cie-panel__dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--color-border);
  flex-shrink: 0;
}

.cie-panel__label {
  margin-left: var(--space-xs);
  opacity: 0.7;
}

.cie-panel__body {
  padding: 24px 20px;
  overflow-x: auto;
}

.cie-expression {
  font-family: var(--font-mono);
  font-size: 0.83rem;
  line-height: 2.1;
  color: var(--color-text);
  white-space: pre;
  position: relative;
  overflow: visible;
}

/* Annotatable token */
.cie-token {
  position: relative;
  color: var(--color-accent);
  cursor: help;
  border-bottom: 1px dashed rgba(0, 188, 212, 0.45);
  transition: background var(--duration-fast) ease;
  border-radius: 2px;
  padding: 0 1px;
}

.cie-token:hover,
.cie-token.is-active {
  background: var(--color-accent-dim);
}

/* Token colour variants */
.cie-token--entity   { color: #c8d8e8; }
.cie-token--operator { color: var(--color-accent); }
.cie-token--ref      { color: #8899aa; }
.cie-token--temporal { color: #a8c4d8; }

/* Tooltip */
.cie-tooltip {
  position: absolute;
  bottom: calc(100% + 9px);
  left: 50%;
  transform: translateX(-50%);
  background: #1a2535;
  border: 1px solid var(--color-border);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 0.72rem;
  line-height: 1.5;
  padding: 7px 11px;
  white-space: nowrap;
  pointer-events: none;
  z-index: 200;
  opacity: 0;
  transition: opacity var(--duration-fast) ease;
  border-radius: 2px;
}

.cie-tooltip::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 5px solid transparent;
  border-top-color: #1a2535;
}

.cie-token:hover .cie-tooltip,
.cie-token.is-active .cie-tooltip {
  opacity: 1;
}

/* Translation line */
.cie-panel__translation {
  padding: 14px 20px;
  border-top: 1px solid var(--color-border);
  font-family: var(--font-sans);
  font-size: 0.80rem;
  color: var(--color-text-muted);
  font-style: italic;
  line-height: 1.65;
}

.cie-panel__translation strong {
  color: var(--color-text);
  font-style: normal;
  font-weight: 500;
}


/* ── 8. Shared Section Styles ────────────────────────────────── */

.section__label {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.section__label::before {
  content: '';
  display: block;
  width: 24px;
  height: 1px;
  background: var(--color-accent);
  flex-shrink: 0;
}

.section__title {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(1.5rem, 2.5vw, 2.1rem);
  letter-spacing: -0.01em;
  line-height: 1.2;
  margin-bottom: var(--space-lg);
  color: var(--color-text);
}

.section__prose p {
  font-size: 1rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
  line-height: 1.85;
  max-width: 680px;
}

.section__prose p strong {
  color: var(--color-text);
  font-weight: 500;
}


/* ── 9. Problem Section ──────────────────────────────────────── */

.section--problem {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}


/* ── 10. Methodology Section ─────────────────────────────────── */

.methodology-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
  position: relative;
  margin-top: var(--space-lg);
}

.methodology-grid::before {
  content: '';
  position: absolute;
  top: 16px;
  left: calc(16.66% + 16px);
  right: calc(16.66% + 16px);
  height: 1px;
  background: var(--color-border);
  z-index: 0;
}

.methodology-step {
  position: relative;
  z-index: 1;
}

.step__number {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--color-accent);
  letter-spacing: 0.08em;
  width: 32px;
  height: 32px;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-md);
}

.step__title {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
  letter-spacing: 0.01em;
}

.step__desc {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.75;
}


/* ── 11. Events Section ──────────────────────────────────────── */

.events-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
  margin-top: var(--space-lg);
}

.event-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: var(--space-lg);
  transition: border-color var(--duration-fast) ease;
}

.event-card:hover {
  border-color: rgba(0, 188, 212, 0.32);
}

.event-card__id {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--color-text-muted);
  letter-spacing: 0.14em;
  margin-bottom: 10px;
  text-transform: uppercase;
  opacity: 0.7;
}

.event-card__cie {
  font-family: var(--font-mono);
  font-size: 0.80rem;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
  line-height: 1.9;
  white-space: pre-wrap;
  word-break: break-word;
}

.event-card__footer {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-md);
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-md);
  flex-wrap: wrap;
}

.event-card__summary {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.7;
  flex: 1;
}

.event-card__tag {
  font-family: var(--font-mono);
  font-size: 0.60rem;
  padding: 3px 9px;
  background: var(--color-accent-dim);
  color: var(--color-accent);
  border: 1px solid rgba(0, 188, 212, 0.18);
  letter-spacing: 0.10em;
  text-transform: uppercase;
  white-space: nowrap;
  flex-shrink: 0;
  align-self: flex-start;
}


/* ── 12. Alpha Section ───────────────────────────────────────── */

.alpha-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-accent);
  padding: var(--space-xl);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  flex-wrap: wrap;
}

.alpha-card__content {
  flex: 1;
  min-width: 280px;
}

.alpha-card__content .section__title {
  margin-bottom: var(--space-sm);
}

.alpha-card__body {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  line-height: 1.8;
  max-width: 560px;
}

.alpha-card__action {
  flex-shrink: 0;
}


/* ── 13. Footer ──────────────────────────────────────────────── */

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
}

.site-footer .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.site-footer__copy {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--color-text-muted);
  letter-spacing: 0.10em;
  opacity: 0.55;
}


/* ── 14. Animations ──────────────────────────────────────────── */

@keyframes fade-up {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.anim-fade-up {
  opacity: 0;
  animation: fade-up 0.75s var(--ease-out-expo) forwards;
}

.anim-delay-1 { animation-delay: 0.10s; }
.anim-delay-2 { animation-delay: 0.25s; }
.anim-delay-3 { animation-delay: 0.40s; }
.anim-delay-4 { animation-delay: 0.55s; }
.anim-delay-5 { animation-delay: 0.70s; }


/* ── 15. Responsive Breakpoints ──────────────────────────────── */

/* Tablet ≤ 1099px */
@media (max-width: 1099px) {
  :root {
    --gutter: 28px;
    --space-2xl: 80px;
  }

  .hero .container {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .hero {
    min-height: auto;
    padding-top: calc(var(--header-height) + 56px);
    padding-bottom: var(--space-xl);
  }

  .hero__subhead {
    max-width: 100%;
  }

  .methodology-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .methodology-grid::before {
    display: none;
  }

  .alpha-card {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* Mobile ≤ 639px */
@media (max-width: 639px) {
  :root {
    --gutter: 16px;
    --space-xl:  48px;
    --space-2xl: 64px;
  }

  .hero {
    padding-top: calc(var(--header-height) + 40px);
  }

  .hero__title {
    font-size: 1.75rem;
  }

  .hero__ctas {
    flex-direction: column;
    align-items: stretch;
  }

  .hero__ctas .btn-primary,
  .hero__ctas .btn-ghost {
    text-align: center;
  }

  .cie-panel__body {
    padding: 16px 14px;
    overflow-x: auto;
  }

  .cie-expression {
    font-size: 0.72rem;
  }

  /* On mobile, tooltips appear below the token */
  .cie-tooltip {
    bottom: auto;
    top: calc(100% + 9px);
    font-size: 0.68rem;
    white-space: normal;
    width: 180px;
    text-align: center;
  }

  .cie-tooltip::after {
    top: auto;
    bottom: 100%;
    border-top-color: transparent;
    border-bottom-color: #1a2535;
  }

  .site-header__cta {
    font-size: 0.60rem;
    padding: 7px 12px;
    letter-spacing: 0.08em;
  }

  .alpha-card {
    padding: var(--space-lg);
  }

  .event-card {
    padding: var(--space-md);
  }

  .event-card__footer {
    flex-direction: column;
  }

  .site-footer .container {
    flex-direction: column;
    align-items: flex-start;
  }
}


/* ══════════════════════════════════════════════════════════════
   MULTI-SECTION EXPANSION — appended styles
   ══════════════════════════════════════════════════════════════ */


/* ── 16. Page Section Routing ────────────────────────────────── */

.page-section {
  display: none;
}

.page-section.is-active {
  display: block;
}


/* ── 17. Site Nav ────────────────────────────────────────────── */

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav__link {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  padding: 6px 14px;
  border-bottom: 1px solid transparent;
  transition:
    color var(--duration-fast) ease,
    border-color var(--duration-fast) ease;
}

.site-nav__link:hover {
  color: var(--color-text);
}

.site-nav__link.is-active {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* Right side of header: hamburger + CTA grouped */
.site-header__right {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* Hamburger button */
.hamburger {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 1rem;
  line-height: 1;
  padding: 6px 10px;
  cursor: pointer;
  transition: color var(--duration-fast) ease, border-color var(--duration-fast) ease;
}

.hamburger:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}


/* ── 18. Prose Layout (deep-dive pages) ──────────────────────── */

.prose-layout {
  max-width: 720px;
  margin: 0 auto;
}

.prose-layout h3 {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 1rem;
  color: var(--color-text);
  letter-spacing: 0.01em;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
}

.prose-layout p {
  font-size: 1rem;
  color: var(--color-text-muted);
  line-height: 1.85;
  margin-bottom: var(--space-md);
}

.prose-layout p strong {
  color: var(--color-text);
  font-weight: 500;
}

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


/* ── 19. Pull Quote ──────────────────────────────────────────── */

.pull-quote {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--color-accent);
  line-height: 1.65;
  border-left: 3px solid var(--color-accent);
  padding: 4px 0 4px 24px;
  margin: var(--space-xl) 0;
  opacity: 0.85;
}

.pull-quote cite {
  display: block;
  font-family: var(--font-sans);
  font-style: normal;
  font-size: 0.78rem;
  color: var(--color-text-muted);
  letter-spacing: 0.08em;
  margin-top: 10px;
}


/* ── 20. Deep Page Hero ──────────────────────────────────────── */

.page-hero {
  padding-top: calc(var(--header-height) + var(--space-xl));
  padding-bottom: var(--space-xl);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-2xl);
}

.page-hero__label {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.page-hero__label::before {
  content: '';
  display: block;
  width: 24px;
  height: 1px;
  background: var(--color-accent);
  flex-shrink: 0;
}

.page-hero__headline {
  font-family: var(--font-sans);
  font-weight: 300;
  font-size: clamp(1.9rem, 3.2vw, 2.9rem);
  line-height: 1.18;
  letter-spacing: -0.015em;
  color: var(--color-text);
  max-width: 780px;
}

.page-hero__headline strong {
  font-weight: 600;
  color: #ffffff;
}


/* ── 21. Page Section Inner Sections ─────────────────────────── */

.prose-section {
  margin-bottom: var(--space-xl);
}

.page-section__cta-wrap {
  margin-top: var(--space-xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border);
}

.page-section__cta-link {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  transition: gap var(--duration-fast) ease;
}

.page-section__cta-link:hover {
  gap: var(--space-md);
}


/* ── 22. Hierarchy Diagram ───────────────────────────────────── */

.hierarchy-diagram {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1;
  margin: var(--space-xl) 0;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-accent);
  padding: var(--space-lg);
}

.hierarchy-layer {
  display: flex;
  gap: var(--space-lg);
  padding: var(--space-md) 0;
  border-bottom: 1px solid rgba(255,255,255,0.04);
  align-items: flex-start;
}

.hierarchy-layer:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.hierarchy-layer__indent {
  color: var(--color-border);
  flex-shrink: 0;
  user-select: none;
  letter-spacing: -0.05em;
}

.hierarchy-layer__code {
  color: var(--color-accent);
  min-width: 110px;
  flex-shrink: 0;
  font-weight: 500;
}

.hierarchy-layer__def {
  color: var(--color-text-muted);
  font-family: var(--font-sans);
  font-size: 0.82rem;
  line-height: 1.6;
}

.hierarchy-layer__def strong {
  color: var(--color-text);
  font-weight: 500;
}


/* ── 23. Annotator Intro (methodology page) ──────────────────── */

.annotator-intro {
  font-size: 1rem;
  color: var(--color-text-muted);
  line-height: 1.8;
  margin-bottom: var(--space-lg);
  max-width: 720px;
}

.annotator-intro strong {
  color: var(--color-text);
  font-weight: 500;
}

.annotator-wrap {
  max-width: 640px;
  margin-bottom: var(--space-xl);
}


/* ── 24. Action Code Table ───────────────────────────────────── */

.action-table-wrap {
  margin: var(--space-lg) 0 var(--space-xl);
  overflow-x: auto;
}

.action-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 0.78rem;
}

.action-table th {
  text-align: left;
  font-size: 0.60rem;
  letter-spacing: 0.20em;
  text-transform: uppercase;
  color: var(--color-accent);
  padding: 10px 16px 10px 0;
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}

.action-table td {
  padding: 12px 16px 12px 0;
  border-bottom: 1px solid rgba(30, 45, 61, 0.6);
  vertical-align: top;
  line-height: 1.55;
}

.action-table tr:last-child td {
  border-bottom: none;
}

.action-table .col-code {
  color: var(--color-accent);
  font-weight: 500;
  white-space: nowrap;
  min-width: 60px;
}

.action-table .col-cat {
  color: var(--color-text-muted);
  white-space: nowrap;
  min-width: 160px;
  font-size: 0.72rem;
}

.action-table .col-name {
  color: var(--color-text);
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 0.82rem;
  min-width: 130px;
}

.action-table .col-desc {
  color: var(--color-text-muted);
  font-family: var(--font-sans);
  font-size: 0.82rem;
  min-width: 280px;
}


/* ── 25. Responsive: Nav + Hamburger ─────────────────────────── */

/* Tablet/mobile hamburger threshold */
@media (max-width: 767px) {

  .hamburger {
    display: block;
    order: 1;
  }

  .site-header__cta {
    display: none;
  }

  /* Nav collapses — hidden by default */
  .site-nav {
    display: none;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: rgba(10, 14, 19, 0.97);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-md) var(--gutter);
    z-index: 99;
  }

  /* Nav open state (JS toggles .is-open) */
  .site-nav.is-open {
    display: flex;
  }

  .site-nav__link {
    padding: 14px 0;
    font-size: 0.75rem;
    width: 100%;
    border-bottom: 1px solid rgba(30, 45, 61, 0.5);
    border-left: none;
    letter-spacing: 0.14em;
  }

  .site-nav__link:last-child {
    border-bottom: none;
  }

  .site-nav__link.is-active {
    border-bottom-color: rgba(30, 45, 61, 0.5);
  }

  .site-nav__link.is-active::before {
    content: '▶ ';
    color: var(--color-accent);
    font-size: 0.5rem;
    vertical-align: middle;
    margin-right: 4px;
  }

  /* Page hero responsive */
  .page-hero {
    padding-top: calc(var(--header-height) + 40px);
    margin-bottom: var(--space-xl);
  }

  /* Prose layout padding */
  .prose-layout {
    max-width: 100%;
  }

  /* Hierarchy diagram scrollable */
  .hierarchy-diagram {
    font-size: 0.72rem;
    overflow-x: auto;
  }

  .hierarchy-layer {
    flex-wrap: wrap;
    gap: var(--space-sm);
  }
}

@media (max-width: 639px) {

  .page-hero__headline {
    font-size: 1.65rem;
  }

  .pull-quote {
    font-size: 0.88rem;
  }

  .action-table {
    font-size: 0.70rem;
  }

  .action-table th {
    font-size: 0.55rem;
  }
}