/* lash docs · canonical stylesheet · warm-iron / fast-amber */

@import url('https://fonts.googleapis.com/css2?family=Big+Shoulders+Display:wght@500;600;700;800;900&family=Chivo+Mono:wght@300;400;500;700&family=Spectral:wght@400;500;600&display=swap');

:root {
  /* warm-iron neutral ramp · hue ~75 (warm tan) · chroma reduced at extremes
     ─ ash-text and chalk-dim are tuned to clear WCAG AA against --form */
  --form-deep:    oklch(0.13 0.003 75);
  --form:         oklch(0.16 0.004 75);
  --form-raised:  oklch(0.20 0.005 75);
  --surface-hover: oklch(0.23 0.005 75);
  --ash:          oklch(0.27 0.005 75);
  --ash-mid:      oklch(0.36 0.006 75);
  --ash-text:     oklch(0.60 0.012 80);
  --chalk-dim:    oklch(0.66 0.012 80);
  --chalk-mid:    oklch(0.81 0.012 85);
  --chalk:        oklch(0.91 0.018 90);

  /* signal accents */
  --sodium:      oklch(0.74 0.155 65);
  --sodium-soft: oklch(0.80 0.110 65);
  --lichen:      oklch(0.66 0.060 130);
  --info:        oklch(0.68 0.040 245);
  --error:       oklch(0.58 0.180 25);
  --ghost-bar:   oklch(0.24 0.040 70);

  --line:        oklch(0.91 0.018 90 / 0.12);
  --line-strong: oklch(0.74 0.155 65 / 0.32);
  --focus-ring:  0 0 0 2px var(--form), 0 0 0 4px var(--sodium);

  /* 4pt spacing scale */
  --space-3xs: 2px;
  --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: 144px;

  --font-display: "Big Shoulders Display", "Big Shoulders", "Helvetica Neue", sans-serif;
  --font-ui:      "Chivo Mono", ui-monospace, monospace;
  --font-body:    "Spectral", "Iowan Old Style", Georgia, serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

/* ─── skip-to-content (keyboard accessibility) ─── */

.skip-link {
  position: absolute;
  top: -100px;
  left: var(--space-md);
  z-index: 999;
  padding: var(--space-sm) var(--space-md);
  background: var(--sodium);
  color: var(--form-deep);
  font-family: var(--font-ui);
  font-size: 0.86rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}
.skip-link:focus {
  top: var(--space-md);
  text-decoration: none;
  box-shadow: var(--focus-ring);
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--chalk);
  background: linear-gradient(180deg, var(--form-deep), var(--form));
  font-family: var(--font-ui);
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background: repeating-linear-gradient(
    -58deg,
    transparent 0,
    transparent 96px,
    oklch(0.74 0.155 65 / 0.025) 96px,
    oklch(0.74 0.155 65 / 0.025) 97px
  );
}

.page {
  position: relative;
  z-index: 1;
  max-width: 1480px;
  margin: 0 auto;
  padding: var(--space-xl);
}

.frame {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  grid-template-areas:
    "sidebar hero"
    "sidebar content"
    "sidebar footer";
  border: 1px solid var(--line);
  background: linear-gradient(180deg, var(--form-raised), var(--form-deep));
  overflow: clip;
}
.sidebar { grid-area: sidebar; }
.hero    { grid-area: hero; }
.content { grid-area: content; }
.footer  { grid-area: footer; }

.hero {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
  padding: var(--space-3xl) var(--space-3xl) var(--space-2xl);
  border-bottom: 1px solid var(--line);
}
.hero:has(.hero-meta) {
  grid-template-columns: minmax(0, 1.18fr) minmax(280px, 0.82fr);
}
.hero > * { position: relative; z-index: 1; }

.eyebrow,
.micro-label,
.card small,
.nav-card small,
.panel small,
.table caption {
  display: inline-block;
  font-family: var(--font-ui);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--ash-text);
}
.panel small {
  margin-bottom: var(--space-xs);
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.02em;
}
h1 {
  margin: var(--space-md) 0 var(--space-sm);
  font-size: clamp(3rem, 7vw, 5.4rem);
  font-weight: 800;
  line-height: 0.92;
  letter-spacing: -0.03em;
  text-transform: uppercase;
  overflow-wrap: anywhere;
}
h2 {
  margin: 0 0 var(--space-sm);
  font-size: clamp(1.8rem, 3.4vw, 2.6rem);
  font-weight: 700;
  line-height: 0.96;
  text-transform: uppercase;
}
h3 {
  margin: 0 0 var(--space-xs);
  font-size: 1.2rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--chalk);
  text-transform: none;
}
h4 {
  margin: 0 0 var(--space-2xs);
  font-size: 1rem;
  font-weight: 600;
  color: var(--chalk);
}

p,
li {
  color: var(--chalk-mid);
  line-height: 1.66;
}
p {
  font-family: var(--font-body);
  font-size: 1.05rem;
  max-width: 72ch;
}
ul {
  margin: var(--space-sm) 0 0;
  padding-left: 1.2rem;
}
li + li { margin-top: var(--space-2xs); }

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

code,
.mono {
  color: var(--chalk);
  background: oklch(0.91 0.018 90 / 0.06);
  border: 1px solid oklch(0.91 0.018 90 / 0.08);
  padding: 0.06rem 0.32rem;
  font-family: var(--font-ui);
  font-size: 0.94em;
}
pre {
  margin: 0;
  padding: var(--space-md);
  overflow-x: auto;
  border: 1px solid var(--line);
  background: var(--form-deep);
  color: var(--chalk-mid);
  line-height: 1.55;
}
.slash,
.accent { color: var(--sodium); }

/* ─── grids ─── */

.hero-meta,
.mode-grid,
.module-grid,
.two-col,
.stats {
  display: grid;
  gap: var(--space-md);
}
.hero-meta { align-content: start; }
.stats { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.module-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.mode-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.two-col { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }

/* ─── solid panels (no glass) ─── */

.card,
.panel,
.diagram,
.table,
.callout,
.nav-card,
.stat {
  border: 1px solid var(--line);
  background: var(--form-raised);
}
.card,
.callout,
.nav-card,
.panel,
.stat {
  padding: var(--space-md) var(--space-lg);
}
.card strong,
.nav-card strong,
.stat strong {
  display: block;
  margin-top: var(--space-xs);
  color: var(--chalk);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
  letter-spacing: -0.01em;
}
.card > span,
.nav-card > span,
.stat > span:not(.stat-value) {
  display: block;
  margin-top: var(--space-2xs);
  color: var(--chalk-dim);
  font-family: var(--font-body);
  font-size: 0.94rem;
  line-height: 1.55;
}
.stat-value {
  display: block;
  margin-top: var(--space-xs);
  color: var(--chalk);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 2rem;
  line-height: 0.95;
  letter-spacing: -0.02em;
}
.stat-note {
  display: block;
  margin-top: var(--space-2xs);
  color: var(--chalk-dim);
  font-size: 0.86rem;
  line-height: 1.5;
  font-family: var(--font-body);
}
.path {
  display: block;
  margin-top: var(--space-sm);
  word-break: break-word;
}

/* ─── editorial principle list (numbered rules, used on multiple pages) ─── */

.principle-list {
  list-style: none;
  counter-reset: pidx;
  margin: 0;
  padding: 0;
  border: 1px solid var(--line);
  border-bottom: none;
  background: var(--form-raised);
}
.principle-list > li {
  counter-increment: pidx;
  display: grid;
  grid-template-columns: 5rem minmax(0, 1fr);
  gap: var(--space-lg);
  padding: var(--space-lg) var(--space-xl);
  border-bottom: 1px solid var(--line);
}
.principle-list > li::before {
  content: counter(pidx, decimal-leading-zero);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 2.4rem;
  line-height: 0.85;
  color: var(--sodium);
  letter-spacing: -0.04em;
}
.principle-list h3 {
  margin: 0 0 var(--space-2xs);
  font-size: 1.34rem;
  color: var(--chalk);
  letter-spacing: -0.01em;
}
.principle-list p {
  margin: var(--space-2xs) 0 0;
  color: var(--chalk-mid);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.66;
  max-width: 64ch;
}
.principle-list ul {
  margin: var(--space-sm) 0 0;
  padding-left: 1.1rem;
  font-family: var(--font-body);
}
.principle-list ul li {
  color: var(--chalk-mid);
  font-size: 0.96rem;
  line-height: 1.6;
}
.principle-list ul li code {
  font-size: 0.92em;
}

/* ─── definition list (term + body — replaces panel grids for reference content) ─── */

.def-list {
  display: grid;
  grid-template-columns: minmax(180px, 0.42fr) minmax(0, 1fr);
  margin: 0;
  border: 1px solid var(--line);
  border-bottom: none;
  background: var(--form-raised);
}
.def-list dt,
.def-list dd {
  margin: 0;
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--line);
}
.def-list dt {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
  letter-spacing: -0.01em;
  color: var(--chalk);
  align-self: baseline;
}
.def-list dt code {
  font-family: var(--font-ui);
  font-size: 0.94em;
}
.def-list dd {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--chalk-mid);
  max-width: 64ch;
}

/* ─── reading paths (curated entry routes on the index) ─── */

.path-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border: 1px solid var(--line);
  border-bottom: none;
  background: var(--form-raised);
}
.path-list > li {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: var(--space-2xl);
  padding: var(--space-lg) var(--space-xl);
  border-bottom: 1px solid var(--line);
}
.path-eyebrow {
  display: block;
  margin-bottom: var(--space-2xs);
  font-family: var(--font-ui);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--sodium);
}
.path-meta h3 {
  margin: 0 0 var(--space-2xs);
  font-size: 1.34rem;
  color: var(--chalk);
  letter-spacing: -0.01em;
}
.path-meta p {
  margin: 0;
  font-family: var(--font-body);
  color: var(--chalk-mid);
  font-size: 1rem;
  line-height: 1.6;
  max-width: 50ch;
}
.path-route {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: route;
  align-self: center;
}
.path-route li {
  counter-increment: route;
  display: grid;
  grid-template-columns: 2.6rem minmax(0, 1fr);
  align-items: baseline;
  padding: var(--space-2xs) 0;
}
.path-route li::before {
  content: counter(route, decimal-leading-zero);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--ash-text);
  letter-spacing: -0.02em;
}
.path-route a {
  color: var(--chalk);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  transition: color 160ms ease;
}
.path-route a:hover {
  color: var(--sodium);
  text-decoration: none;
}
.path-route a:focus-visible {
  outline: none;
  color: var(--sodium);
  box-shadow: var(--focus-ring);
}

/* ─── persistent left-rail sidebar (chapter index + on-page anchors) ─── */

.sidebar {
  position: sticky;
  top: 0;
  align-self: start;
  max-height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-xl);
  padding: var(--space-xl) var(--space-lg);
  border-right: 1px solid var(--line);
  background: var(--form);
  scrollbar-width: thin;
  scrollbar-color: var(--ash) transparent;
}
.sidebar::-webkit-scrollbar { width: 6px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--ash); }

.sidebar__exit {
  font-family: var(--font-ui);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  color: var(--ash-text);
}
.sidebar__exit:hover {
  color: var(--chalk);
  text-decoration: none;
}
.sidebar__exit:focus-visible {
  outline: none;
  color: var(--chalk);
  box-shadow: var(--focus-ring);
}

.sidebar__label {
  display: block;
  margin-bottom: var(--space-sm);
  font-family: var(--font-ui);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--ash-text);
}

.sidebar__disclosure {
  display: contents; /* on wide, the <details> wrapper doesn't form a box */
}
.sidebar__disclosure > summary {
  list-style: none;
  cursor: default;
  pointer-events: none;
}
.sidebar__disclosure > summary::-webkit-details-marker { display: none; }
.sidebar__current { display: none; }

.sidebar__chapters {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: chap;
}
.sidebar__chapters li {
  counter-increment: chap;
}
.sidebar__chapters a {
  display: grid;
  grid-template-columns: 1.8rem minmax(0, 1fr);
  gap: var(--space-xs);
  align-items: baseline;
  padding: var(--space-2xs) 0;
  color: var(--chalk-mid);
  font-family: var(--font-ui);
  font-size: 0.86rem;
  line-height: 1.5;
  transition: color 160ms ease;
}
.sidebar__chapters a::before {
  content: counter(chap, decimal-leading-zero);
  color: var(--ash-text);
  font-size: 0.74rem;
  letter-spacing: 0.02em;
}
.sidebar__chapters a:hover {
  color: var(--chalk);
  text-decoration: none;
}
.sidebar__chapters a:focus-visible {
  outline: none;
  color: var(--chalk);
  box-shadow: var(--focus-ring);
}
.sidebar__chapters a.active {
  color: var(--sodium);
}
.sidebar__chapters a.active::before {
  color: var(--sodium);
}

.sidebar__toc {
  border-top: 1px solid var(--line);
  padding-top: var(--space-md);
}
.sidebar__toc ol {
  list-style: none;
  margin: 0;
  padding: 0;
}
.sidebar__toc a {
  display: block;
  padding: var(--space-2xs) 0;
  color: var(--chalk-dim);
  font-family: var(--font-ui);
  font-size: 0.78rem;
  line-height: 1.45;
  transition: color 160ms ease;
}
.sidebar__toc a:hover {
  color: var(--sodium);
  text-decoration: none;
}
.sidebar__toc a:focus-visible {
  outline: none;
  color: var(--sodium);
  box-shadow: var(--focus-ring);
}

/* ─── content + sections ─── */

.content {
  padding: var(--space-xl);
}
.section {
  margin-top: var(--space-xl);
}
.section:first-child {
  margin-top: 0;
}
.section-header {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  gap: var(--space-xl);
  align-items: end;
  margin-bottom: var(--space-lg);
}
.section-header h2 {
  margin: 0;
}
.section-header p {
  max-width: 64ch;
  margin: 0;
  font-size: 1.02rem;
}

.diagram {
  position: relative;
  padding: var(--space-md);
  background: var(--form);
}
.diagram-title {
  margin-bottom: var(--space-sm);
  color: var(--ash-text);
  font-size: 0.8rem;
  letter-spacing: 0.04em;
}
.mermaid {
  padding: var(--space-sm);
  border: 1px solid oklch(0.91 0.018 90 / 0.08);
  background: var(--form-deep);
}
.mermaid svg {
  width: 100% !important;
  height: auto !important;
  max-width: 100% !important;
  display: block;
  margin: 0 auto;
}

/* ─── click-to-fullscreen on diagrams (injected by mermaid.js) ─── */

.diagram-zoom {
  position: absolute;
  top: var(--space-sm);
  right: var(--space-sm);
  z-index: 2;
  width: 30px;
  height: 30px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  background: oklch(0.16 0.004 75 / 0.8);
  color: var(--ash-text);
  font-family: var(--font-ui);
  font-size: 14px;
  cursor: pointer;
  transition: color 160ms ease, border-color 160ms ease, background 160ms ease;
}
.diagram-zoom:hover {
  color: var(--sodium);
  border-color: var(--line-strong);
  background: var(--form);
}
.diagram-zoom:focus-visible {
  outline: none;
  color: var(--sodium);
  box-shadow: var(--focus-ring);
}

.diagram-modal {
  display: flex;
  flex-direction: column;
  width: min(95vw, 1600px);
  max-width: 95vw;
  height: min(92vh, 1100px);
  max-height: 92vh;
  margin: auto;
  padding: 0;
  border: 1px solid var(--line);
  background: var(--form);
  color: var(--chalk);
}
.diagram-modal::backdrop {
  background: oklch(0.08 0.003 75 / 0.78);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
.diagram-modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--line);
}
.diagram-modal__title {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--ash-text);
}
.diagram-modal__controls {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}
.diagram-modal__btn {
  border: 1px solid var(--line);
  background: transparent;
  color: var(--chalk-mid);
  padding: var(--space-2xs) var(--space-sm);
  font-family: var(--font-ui);
  font-size: 0.82rem;
  letter-spacing: 0.02em;
  cursor: pointer;
  min-width: 32px;
  transition: color 160ms ease, border-color 160ms ease;
}
.diagram-modal__btn:hover {
  color: var(--chalk);
  border-color: var(--line-strong);
}
.diagram-modal__btn:focus-visible {
  outline: none;
  color: var(--chalk);
  box-shadow: var(--focus-ring);
}
.diagram-modal__zoom {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  color: var(--ash-text);
  min-width: 4ch;
  text-align: center;
}
.diagram-modal__body {
  flex: 1;
  position: relative;
  overflow: hidden;
  background: var(--form-deep);
  cursor: grab;
}
.diagram-modal__body.is-panning {
  cursor: grabbing;
}
.diagram-modal__stage {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  transform-origin: 0 0;
  transition: transform 0ms;
  will-change: transform;
}
.diagram-modal__body svg {
  width: 100% !important;
  height: 100% !important;
  max-width: none !important;
  max-height: none !important;
  display: block;
}

.table {
  overflow-x: auto;
}
table {
  width: 100%;
  border-collapse: collapse;
}
th,
td {
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  text-align: left;
}
th {
  color: var(--sodium);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.86rem;
  letter-spacing: 0.01em;
}
td {
  color: var(--chalk-mid);
  line-height: 1.55;
  font-size: 0.96rem;
}

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-top: var(--space-sm);
}
.pill {
  border: 1px solid var(--line);
  color: var(--chalk-dim);
  background: oklch(0.91 0.018 90 / 0.04);
  padding: var(--space-2xs) var(--space-xs);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
}

.status {
  display: inline-flex;
  gap: var(--space-xs);
  align-items: center;
  padding: var(--space-2xs) var(--space-xs);
  border: 1px solid var(--line);
  color: var(--chalk-mid);
  background: oklch(0.91 0.018 90 / 0.04);
  font-size: 0.78rem;
}
.status::before {
  content: "";
  width: 7px;
  height: 7px;
  background: var(--lichen);
}
.warn::before { background: var(--sodium); }
.danger::before { background: var(--error); }

.section-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  margin-top: var(--space-2xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--line);
}
.section-nav > * { flex: 1 1 0; max-width: 340px; }
.section-nav > *:last-child { text-align: right; }
.section-nav a {
  display: block;
  color: var(--chalk-mid);
  transition: color 160ms ease;
}
.section-nav a:hover {
  text-decoration: none;
}
.section-nav a:hover strong {
  color: var(--sodium);
}
.section-nav span {
  display: block;
  margin-bottom: var(--space-2xs);
  color: var(--ash-text);
  font-family: var(--font-ui);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}
.section-nav strong {
  display: block;
  color: var(--chalk);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.34rem;
  letter-spacing: -0.01em;
  transition: color 160ms ease;
}

.footer {
  padding: var(--space-md) var(--space-xl) var(--space-lg);
  border-top: 1px solid var(--line);
  color: var(--ash-text);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
}

@media (max-width: 1024px) {
  .hero,
  .stats,
  .mode-grid,
  .module-grid,
  .two-col,
  .section-header {
    grid-template-columns: 1fr;
  }
  .hero:has(.hero-meta) { grid-template-columns: 1fr; }
  .section-header { gap: var(--space-sm); }
  .path-list > li {
    grid-template-columns: 1fr;
    gap: var(--space-md);
    padding: var(--space-md) var(--space-lg);
  }
  .def-list {
    grid-template-columns: 1fr;
  }
  .def-list dt {
    border-bottom: none;
    padding-bottom: 0;
  }
  .def-list dd {
    padding-top: var(--space-2xs);
  }
  .principle-list > li {
    grid-template-columns: 3.4rem minmax(0, 1fr);
    padding: var(--space-md) var(--space-lg);
  }
  .principle-list > li::before { font-size: 1.8rem; }
  .frame {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas:
      "sidebar"
      "hero"
      "content"
      "footer";
  }
  .sidebar {
    position: static;
    max-height: none;
    overflow: visible;
    border-right: none;
    border-bottom: 1px solid var(--line);
    padding: var(--space-md) var(--space-lg);
    gap: var(--space-md);
  }
  .sidebar__disclosure {
    display: block;
  }
  .sidebar__disclosure > summary {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: var(--space-md);
    cursor: pointer;
    pointer-events: auto;
    padding: var(--space-2xs) 0;
  }
  .sidebar__disclosure > summary .sidebar__label {
    margin-bottom: 0;
  }
  .sidebar__current {
    display: inline-block;
    color: var(--chalk);
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: -0.01em;
  }
  .sidebar__disclosure > summary::after {
    content: "▾";
    margin-left: auto;
    color: var(--ash-text);
    transition: transform 160ms ease;
  }
  .sidebar__disclosure[open] > summary::after {
    transform: rotate(180deg);
  }
  .sidebar__disclosure:not([open]) > .sidebar__chapters {
    display: none;
  }
  .sidebar__chapters {
    margin-top: var(--space-sm);
  }
  .sidebar__toc { display: none; }
}

@media (max-width: 720px) {
  .page { padding: var(--space-md); }
  .hero { padding: var(--space-xl) var(--space-lg); }
  .content { padding: var(--space-lg) var(--space-md); }
  h1 { font-size: clamp(2.2rem, 9vw, 3rem); }
  .section-nav { flex-direction: column; }
  .section-nav a { max-width: none; }
  .path-list > li {
    padding: var(--space-md);
    gap: var(--space-sm);
  }
  .path-route a { font-size: 1rem; }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}