:root {
  color-scheme: dark;
  --bg: #0c0c0a;
  --surface: #141410;
  --surface-2: #1c1c17;
  --surface-3: #242420;
  --surface-inset: #10100d;
  --border: #2e2e26;
  --border-high: #45453a;
  --text: #f5f0e8;
  --text-soft: #d2ccbe;
  --muted: #a69e8f;
  --dim: #81796c;
  --faint: #625c52;
  --cyan: #00d4ff;
  --cyan-soft: rgba(0, 212, 255, 0.1);
  --red: #ff3b5c;
  --red-soft: rgba(255, 59, 92, 0.11);
  --green: #22c55e;
  --green-soft: rgba(34, 197, 94, 0.11);
  --amber: #f59e0b;
  --amber-soft: rgba(245, 158, 11, 0.11);
  --blue: #60a5fa;
  --purple: #c084fc;
  --danger: #ef4444;
  --radius-sm: 7px;
  --radius-md: 11px;
  --radius-lg: 15px;
  --rail-width: 318px;
  --topbar-height: 52px;
  --content-width: 900px;
  --font: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --shadow: 0 18px 60px rgba(0, 0, 0, 0.25);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--topbar-height) + 18px);
}

body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(circle at 72% -20%, rgba(0, 212, 255, 0.055), transparent 34rem),
    var(--bg);
  color: var(--text-soft);
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body.modal-open {
  overflow: hidden;
}

button,
input {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

a {
  color: inherit;
}

svg {
  display: block;
}

::selection {
  background: rgba(0, 212, 255, 0.22);
  color: var(--text);
}

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 1000;
  transform: translateY(-150%);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  background: var(--text);
  color: var(--bg);
  font: 700 12px var(--mono);
  text-decoration: none;
  transition: transform 0.15s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.reading-progress {
  position: fixed;
  inset: 0 0 auto;
  z-index: 500;
  height: 2px;
  pointer-events: none;
}

.reading-progress span {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--green));
  box-shadow: 0 0 12px rgba(0, 212, 255, 0.45);
  transition: width 0.08s linear;
}

/* Top bar */
.topbar {
  position: sticky;
  top: 0;
  z-index: 100;
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(0, 1fr) minmax(220px, 1fr);
  align-items: center;
  min-height: var(--topbar-height);
  padding: 7px 16px;
  border-bottom: 1px solid var(--border);
  background: rgba(12, 12, 10, 0.94);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.topbar-start,
.topbar-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
}

.topbar-actions {
  justify-content: flex-end;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 8px;
  min-width: 0;
  text-decoration: none;
}

.brand strong {
  color: var(--cyan);
  font: 700 13px var(--mono);
  letter-spacing: -0.025em;
  white-space: nowrap;
}

.brand span {
  overflow: hidden;
  color: var(--dim);
  font-size: 11px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.current-location {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-width: 0;
  color: var(--muted);
  font: 600 11px var(--mono);
  letter-spacing: 0.02em;
  text-align: center;
}

.current-location span:last-child {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.current-prefix {
  color: var(--cyan);
  font-weight: 700;
}

.icon-button,
.search-button,
.ecosystem-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 34px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  text-decoration: none;
  cursor: pointer;
  transition: color 0.15s ease, border-color 0.15s ease, background 0.15s ease, transform 0.15s ease;
}

.icon-button {
  width: 36px;
  min-width: 36px;
  padding: 0;
  border-radius: 8px;
}

.icon-button svg,
.search-button svg {
  width: 17px;
  height: 17px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.github-link svg {
  fill: currentColor;
  stroke: none;
}

.icon-button:hover,
.search-button:hover,
.ecosystem-link:hover {
  transform: translateY(-1px);
  border-color: var(--border-high);
  background: var(--surface-2);
  color: var(--text);
}

.menu-button {
  display: none;
}

.search-button {
  gap: 7px;
  padding: 0 9px;
  font: 600 10px var(--mono);
}

.search-button kbd,
.search-input-wrap kbd,
.search-footer kbd {
  border: 1px solid var(--border);
  border-bottom-color: var(--border-high);
  border-radius: 4px;
  background: var(--surface-inset);
  color: var(--dim);
  font: 600 9px var(--mono);
  line-height: 1;
  padding: 3px 5px;
  box-shadow: inset 0 -1px 0 rgba(255, 255, 255, 0.03);
}

.ecosystem-link {
  min-height: 30px;
  padding: 0 10px;
  font: 700 9px var(--mono);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.ecosystem-link.forge {
  color: #ff8ca0;
  border-color: rgba(255, 59, 92, 0.28);
  background: var(--red-soft);
}

.ecosystem-link.patterns {
  color: #77e89b;
  border-color: rgba(34, 197, 94, 0.28);
  background: var(--green-soft);
}

/* Primary layout */
.site-shell {
  display: grid;
  grid-template-columns: var(--rail-width) minmax(0, 1fr);
  min-height: calc(100vh - var(--topbar-height));
}

.reading-rail {
  position: sticky;
  top: var(--topbar-height);
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  height: calc(100vh - var(--topbar-height));
  border-right: 1px solid var(--border);
  background: rgba(20, 20, 16, 0.74);
}

.rail-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 17px 17px 13px;
  border-bottom: 1px solid var(--border);
}

.rail-heading p {
  margin: 0;
  color: var(--text);
  font: 700 11px var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.rail-heading span {
  color: var(--dim);
  font: 600 9px var(--mono);
}

.rail-scroll,
.drawer-scroll {
  overflow-y: auto;
  padding: 12px;
  scrollbar-width: thin;
  scrollbar-color: var(--border-high) transparent;
}

.rail-shortcuts {
  display: grid;
  gap: 5px;
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
}

.rail-shortcuts a {
  display: grid;
  gap: 1px;
  padding: 9px 10px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  text-decoration: none;
}

.rail-shortcuts a:hover {
  border-color: var(--border);
  background: var(--surface-2);
}

.rail-shortcuts span {
  color: var(--text);
  font-size: 11px;
  font-weight: 700;
}

.rail-shortcuts small {
  color: var(--dim);
  font-size: 9px;
}

.rail-group {
  margin: 2px 0;
}

.rail-group > summary,
.rail-subgroup > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  list-style: none;
  cursor: pointer;
  user-select: none;
}

.rail-group > summary::-webkit-details-marker,
.rail-subgroup > summary::-webkit-details-marker {
  display: none;
}

.rail-group > summary {
  position: relative;
  padding: 9px 9px 9px 20px;
  border-radius: var(--radius-sm);
  color: var(--muted);
  font: 700 10px var(--mono);
  letter-spacing: 0.02em;
}

.rail-group > summary::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 50%;
  width: 5px;
  height: 5px;
  border-right: 1px solid var(--dim);
  border-bottom: 1px solid var(--dim);
  transform: translateY(-65%) rotate(-45deg);
  transition: transform 0.15s ease;
}

.rail-group[open] > summary::before {
  transform: translateY(-75%) rotate(45deg);
}

.rail-group > summary:hover,
.rail-subgroup > summary:hover {
  background: var(--surface-2);
  color: var(--text);
}

.rail-reference > summary {
  color: var(--text-soft);
}

.rail-count {
  min-width: 24px;
  padding: 2px 6px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface-inset);
  color: var(--dim);
  font-size: 8px;
  text-align: center;
}

.rail-subgroup {
  margin: 2px 0 2px 9px;
  padding-left: 7px;
  border-left: 1px solid var(--border);
}

.rail-subgroup > summary {
  padding: 6px 7px;
  border-radius: 5px;
  color: var(--dim);
  font: 600 9px var(--mono);
}

.rail-subgroup > summary span {
  color: var(--faint);
  font-size: 8px;
}

.rail-link {
  position: relative;
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 3px;
  align-items: start;
  margin: 1px 0;
  padding: 7px 8px;
  border: 1px solid transparent;
  border-radius: 6px;
  color: var(--muted);
  font-size: 10px;
  line-height: 1.35;
  text-decoration: none;
  transition: color 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}

.rail-link:hover {
  border-color: var(--border);
  background: var(--surface-2);
  color: var(--text);
}

.rail-link.active {
  border-color: rgba(0, 212, 255, 0.18);
  background: var(--cyan-soft);
  color: var(--text);
}

.rail-link.active::before {
  content: "";
  position: absolute;
  inset: 6px auto 6px -1px;
  width: 2px;
  border-radius: 2px;
  background: var(--cyan);
}

.rail-number {
  color: var(--faint);
  font: 700 8px var(--mono);
  text-align: right;
}

.rail-link.active .rail-number {
  color: var(--cyan);
}

.rail-footer {
  padding: 13px 17px 16px;
  border-top: 1px solid var(--border);
  color: var(--dim);
  font-size: 9px;
}

.rail-footer p {
  margin: 0 0 5px;
}

.rail-footer a {
  color: var(--muted);
  text-decoration: none;
}

.rail-footer a:hover {
  color: var(--cyan);
}

main {
  min-width: 0;
  overflow: clip;
}

/* Hero */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(300px, 0.75fr);
  gap: clamp(28px, 6vw, 72px);
  align-items: end;
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
  padding: clamp(54px, 8vw, 92px) 0 34px;
}

.eyebrow,
.section-kicker {
  margin: 0;
  color: var(--cyan);
  font: 700 9px var(--mono);
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 760px;
  margin: 10px 0 0;
  color: var(--text);
  font-size: clamp(37px, 5.3vw, 68px);
  font-weight: 700;
  letter-spacing: -0.055em;
  line-height: 1.02;
}

.hero-lead {
  max-width: 760px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: clamp(14px, 1.4vw, 17px);
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-top: 25px;
}

.primary-action,
.secondary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 8px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}

.primary-action {
  border-color: rgba(0, 212, 255, 0.32);
  background: var(--cyan-soft);
  color: #7eeaff;
}

.secondary-action {
  background: var(--surface);
  color: var(--text);
}

.primary-action:hover,
.secondary-action:hover {
  border-color: var(--border-high);
  background: var(--surface-2);
}

.inventory-panel {
  padding: 17px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, var(--surface-2), var(--surface));
  box-shadow: var(--shadow);
}

.inventory-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 13px;
  color: var(--muted);
  font: 700 9px var(--mono);
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.status-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 7px;
  border: 1px solid rgba(34, 197, 94, 0.3);
  border-radius: 999px;
  background: var(--green-soft);
  color: #7ee7a2;
  font-size: 8px;
}

.status-chip i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 8px rgba(34, 197, 94, 0.5);
}

.inventory-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 7px;
}

.inventory-grid a {
  min-height: 80px;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: rgba(12, 12, 10, 0.4);
  text-decoration: none;
}

.inventory-grid a:hover {
  border-color: var(--border-high);
  background: var(--surface-3);
}

.inventory-grid strong {
  display: block;
  color: var(--text);
  font: 700 20px var(--mono);
}

.inventory-grid span {
  display: block;
  margin-top: 5px;
  color: var(--dim);
  font-size: 9px;
}

.inventory-panel > p {
  margin: 12px 1px 0;
  color: var(--dim);
  font-size: 9px;
}

.route-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 9px;
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto 58px;
}

.route-card {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr) auto;
  gap: 12px;
  align-items: start;
  min-height: 132px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface);
  text-decoration: none;
  transition: transform 0.15s ease, border-color 0.15s ease, background 0.15s ease;
}

.route-card:hover {
  transform: translateY(-2px);
  border-color: var(--border-high);
  background: var(--surface-2);
}

.route-code {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid rgba(0, 212, 255, 0.22);
  border-radius: 8px;
  background: var(--cyan-soft);
  color: var(--cyan);
  font: 700 11px var(--mono);
}

.route-card[data-tone="amber"] .route-code {
  border-color: rgba(245, 158, 11, 0.23);
  background: var(--amber-soft);
  color: var(--amber);
}

.route-card[data-tone="green"] .route-code {
  border-color: rgba(34, 197, 94, 0.23);
  background: var(--green-soft);
  color: var(--green);
}

.route-card strong {
  display: block;
  color: var(--text);
  font-size: 13px;
}

.route-card p {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 10px;
  line-height: 1.55;
}

.route-arrow {
  color: var(--dim);
  font-size: 18px;
}

/* Content */
.content-stream {
  width: 100%;
  padding-bottom: 68px;
}

.part-divider,
.content-card {
  width: min(var(--content-width), calc(100% - 48px));
  margin-inline: auto;
}

.part-divider {
  position: relative;
  margin-top: 76px;
  margin-bottom: 18px;
  padding: 24px 22px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: linear-gradient(115deg, var(--surface-2), rgba(20, 20, 16, 0.7));
  scroll-margin-top: calc(var(--topbar-height) + 20px);
}

.part-divider::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  border-radius: var(--radius-md) 0 0 var(--radius-md);
  background: var(--cyan);
}

.part-divider.reference-divider::before {
  background: linear-gradient(var(--green), var(--cyan));
}

.part-divider h2 {
  margin: 8px 0 5px;
  color: var(--text);
  font-size: clamp(22px, 3vw, 32px);
  letter-spacing: -0.035em;
  line-height: 1.15;
}

.part-divider > p:last-of-type {
  max-width: 690px;
  margin: 0;
  color: var(--muted);
  font-size: 12px;
}

.part-count {
  position: absolute;
  top: 22px;
  right: 21px;
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface-inset);
  color: var(--dim);
  font: 600 8px var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.content-card {
  margin-top: 12px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
  scroll-margin-top: calc(var(--topbar-height) + 18px);
}

.content-card:target {
  border-color: rgba(0, 212, 255, 0.42);
  box-shadow: 0 0 0 1px rgba(0, 212, 255, 0.08), 0 18px 55px rgba(0, 0, 0, 0.25);
}

.chapter-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 47px;
  padding: 10px 19px;
  border-bottom: 1px solid var(--border);
  background: rgba(28, 28, 23, 0.62);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.chapter-tools {
  display: flex;
  align-items: center;
  gap: 5px;
}

.chapter-tools button,
.chapter-tools a {
  padding: 5px 8px;
  border: 1px solid transparent;
  border-radius: 5px;
  background: transparent;
  color: var(--dim);
  font: 600 8px var(--mono);
  text-decoration: none;
  cursor: pointer;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.chapter-tools button:hover,
.chapter-tools a:hover {
  border-color: var(--border);
  background: var(--surface-3);
  color: var(--text);
}

.chapter-body {
  padding: clamp(25px, 5vw, 50px);
}

.chapter-body > :first-child {
  margin-top: 0;
}

.chapter-body > :last-child {
  margin-bottom: 0;
}

.chapter-body h1 {
  margin: 0 0 23px;
  color: var(--text);
  font-size: clamp(28px, 4.2vw, 43px);
  font-weight: 700;
  letter-spacing: -0.045em;
  line-height: 1.08;
}

.chapter-body h2,
.chapter-body h3 {
  scroll-margin-top: calc(var(--topbar-height) + 22px);
}

.chapter-body h2 {
  margin: 42px 0 15px;
  padding-bottom: 9px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  font-size: 22px;
  letter-spacing: -0.025em;
  line-height: 1.25;
}

.chapter-body h2::before {
  content: "//";
  margin-right: 8px;
  color: var(--cyan);
  font: 700 0.67em var(--mono);
  letter-spacing: 0;
}

.chapter-body h3 {
  margin: 30px 0 11px;
  color: var(--text);
  font-size: 17px;
  letter-spacing: -0.015em;
}

.chapter-body h4,
.chapter-body h5,
.chapter-body h6 {
  margin: 24px 0 9px;
  color: var(--muted);
  font: 700 11px var(--mono);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.chapter-body p {
  margin: 0 0 16px;
}

.chapter-body strong {
  color: var(--text);
  font-weight: 700;
}

.chapter-body em {
  color: var(--muted);
}

.chapter-body a {
  color: #6ce6ff;
  text-decoration: underline;
  text-decoration-color: rgba(0, 212, 255, 0.35);
  text-underline-offset: 3px;
}

.chapter-body a:hover {
  color: var(--text);
  text-decoration-color: var(--cyan);
}

.chapter-body ul,
.chapter-body ol {
  margin: 0 0 18px;
  padding-left: 23px;
}

.chapter-body li {
  margin: 6px 0;
  padding-left: 3px;
}

.chapter-body li::marker {
  color: var(--cyan);
  font-family: var(--mono);
}

.chapter-body hr {
  height: 1px;
  margin: 38px 0;
  border: 0;
  background: var(--border);
}

.chapter-body blockquote {
  margin: 23px 0;
  padding: 14px 17px;
  border: 1px solid var(--border);
  border-left: 3px solid var(--cyan);
  border-radius: 0 8px 8px 0;
  background: var(--surface-2);
  color: var(--muted);
}

.chapter-body blockquote p:last-child {
  margin-bottom: 0;
}

.chapter-body code {
  padding: 0.13em 0.34em;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--surface-inset);
  color: #8fe9ff;
  font: 500 0.88em var(--mono);
}

.chapter-body pre,
.chapter-body .codehilite {
  max-width: 100%;
  overflow-x: auto;
  margin: 22px 0;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: var(--surface-inset);
  scrollbar-width: thin;
}

.chapter-body pre {
  padding: 17px;
}

.chapter-body .codehilite pre {
  margin: 0;
  border: 0;
  border-radius: inherit;
}

.chapter-body pre code,
.chapter-body .codehilite code {
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--text-soft);
  font-size: 12px;
  line-height: 1.6;
}

.chapter-body table {
  display: block;
  width: max-content;
  max-width: 100%;
  overflow-x: auto;
  margin: 23px 0;
  border: 1px solid var(--border);
  border-collapse: separate;
  border-spacing: 0;
  border-radius: 9px;
  background: var(--surface-inset);
  scrollbar-width: thin;
}

.chapter-body th,
.chapter-body td {
  min-width: 112px;
  padding: 10px 12px;
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  vertical-align: top;
  text-align: left;
  font-size: 11px;
}

.chapter-body th {
  position: sticky;
  top: 0;
  background: var(--surface-2);
  color: var(--text);
  font: 700 9px var(--mono);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.chapter-body tr:last-child td {
  border-bottom: 0;
}

.chapter-body th:last-child,
.chapter-body td:last-child {
  border-right: 0;
}

.chapter-body img,
.chapter-body svg {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
}

.chapter-body img {
  display: block;
  margin: 24px auto;
  border: 1px solid var(--border);
  background: var(--surface-inset);
}

.chapter-pager {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  border-top: 1px solid var(--border);
  background: var(--border);
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  overflow: hidden;
}

.chapter-step {
  display: grid;
  align-content: center;
  min-height: 82px;
  padding: 14px 20px;
  background: var(--surface-2);
  text-decoration: none;
}

.chapter-step.next {
  text-align: right;
}

.chapter-step:hover {
  background: var(--surface-3);
}

.chapter-step.empty {
  background: var(--surface);
}

.step-label {
  color: var(--dim);
  font: 700 8px var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.chapter-step strong {
  margin-top: 3px;
  color: var(--text-soft);
  font-size: 11px;
  line-height: 1.35;
}

.chapter-step:hover strong {
  color: var(--cyan);
}

.site-footer {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  width: min(1180px, calc(100% - 48px));
  margin: 72px auto 0;
  padding: 24px 0 42px;
  border-top: 1px solid var(--border);
  color: var(--dim);
  font-size: 10px;
}

.site-footer strong {
  color: var(--muted);
  font-size: 11px;
}

.site-footer p {
  margin: 4px 0 0;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 12px;
}

.site-footer a {
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--cyan);
}

/* Drawer */
.drawer-backdrop {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: rgba(0, 0, 0, 0.68);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}

.drawer-backdrop[hidden],
.search-overlay[hidden] {
  display: none;
}

.nav-drawer {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 301;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  width: min(340px, 90vw);
  border-right: 1px solid var(--border);
  background: var(--surface);
  box-shadow: 20px 0 70px rgba(0, 0, 0, 0.45);
  transform: translateX(-102%);
  visibility: hidden;
  transition: transform 0.22s ease, visibility 0.22s;
}

.nav-drawer.open {
  transform: translateX(0);
  visibility: visible;
}

.drawer-header,
.drawer-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
}

.drawer-header > div {
  display: grid;
}

.drawer-header strong {
  color: var(--cyan);
  font: 700 12px var(--mono);
}

.drawer-header span {
  color: var(--dim);
  font-size: 9px;
}

.drawer-footer {
  justify-content: flex-start;
  border-top: 1px solid var(--border);
  border-bottom: 0;
}

.drawer-footer a {
  color: var(--muted);
  font: 600 9px var(--mono);
  text-decoration: none;
  text-transform: uppercase;
}

.drawer-footer a:hover {
  color: var(--cyan);
}

/* Search */
.search-overlay {
  position: fixed;
  inset: 0;
  z-index: 400;
  display: grid;
  place-items: start center;
  overflow-y: auto;
  padding: min(8vh, 72px) 16px 30px;
  background: rgba(6, 6, 5, 0.82);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.search-dialog {
  width: min(760px, 100%);
  overflow: hidden;
  border: 1px solid var(--border-high);
  border-radius: 14px;
  background: var(--surface);
  box-shadow: 0 30px 100px rgba(0, 0, 0, 0.55);
}

.search-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 17px 18px 14px;
  border-bottom: 1px solid var(--border);
}

.search-head h2 {
  margin: 4px 0 0;
  color: var(--text);
  font-size: 18px;
  letter-spacing: -0.025em;
}

.search-input-wrap {
  position: relative;
  display: flex;
  align-items: center;
  gap: 9px;
  margin: 15px 16px 10px;
  padding: 0 12px;
  border: 1px solid var(--border-high);
  border-radius: 9px;
  background: var(--surface-inset);
}

.search-input-wrap:focus-within {
  border-color: rgba(0, 212, 255, 0.58);
  box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.08);
}

.search-input-wrap svg {
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
  fill: none;
  stroke: var(--dim);
  stroke-width: 1.8;
  stroke-linecap: round;
}

.search-input-wrap input {
  width: 100%;
  min-width: 0;
  height: 47px;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--text);
  font-size: 13px;
}

.search-input-wrap input::placeholder {
  color: var(--faint);
}

.search-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  padding: 0 16px 12px;
  border-bottom: 1px solid var(--border);
}

.search-filters button {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 8px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--dim);
  font: 600 9px var(--mono);
  cursor: pointer;
}

.search-filters button:hover,
.search-filters button.active {
  border-color: rgba(0, 212, 255, 0.28);
  background: var(--cyan-soft);
  color: var(--text);
}

.search-filters span {
  color: var(--faint);
  font-size: 8px;
}

.search-results {
  max-height: min(58vh, 570px);
  overflow-y: auto;
  padding: 7px;
  scrollbar-width: thin;
}

.search-empty {
  display: grid;
  gap: 5px;
  padding: 40px 20px;
  color: var(--dim);
  text-align: center;
}

.search-empty strong {
  color: var(--muted);
  font-size: 12px;
}

.search-empty span {
  font-size: 10px;
}

.search-count {
  padding: 7px 9px 5px;
  color: var(--dim);
  font: 600 8px var(--mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.search-result {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 7px 12px;
  margin: 2px 0;
  padding: 11px 12px;
  border: 1px solid transparent;
  border-radius: 8px;
  text-decoration: none;
  cursor: pointer;
}

.search-result:hover,
.search-result.active {
  border-color: var(--border);
  background: var(--surface-2);
}

.search-result-context {
  grid-column: 1 / -1;
  color: var(--dim);
  font: 600 8px var(--mono);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.search-result-heading {
  color: var(--text);
  font-size: 12px;
  font-weight: 700;
}

.search-result-kind {
  align-self: start;
  padding: 3px 6px;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--dim);
  font: 600 7px var(--mono);
  text-transform: uppercase;
}

.search-result-snippet {
  grid-column: 1 / -1;
  color: var(--muted);
  font-size: 9px;
  line-height: 1.5;
}

.search-result mark {
  border-radius: 2px;
  background: rgba(0, 212, 255, 0.16);
  color: #8eeeff;
}

.search-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 14px;
  padding: 9px 15px;
  border-top: 1px solid var(--border);
  color: var(--dim);
  font-size: 8px;
}

.search-footer span {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

/* Small feedback controls */
.back-to-top {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 90;
  width: 38px;
  height: 38px;
  border: 1px solid var(--border-high);
  border-radius: 9px;
  background: rgba(28, 28, 23, 0.92);
  color: var(--muted);
  font: 700 15px var(--mono);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity 0.15s ease, transform 0.15s ease, color 0.15s ease;
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.back-to-top:hover {
  color: var(--cyan);
}

.toast {
  position: fixed;
  left: 50%;
  bottom: 22px;
  z-index: 450;
  padding: 8px 12px;
  border: 1px solid var(--border-high);
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--text);
  font: 600 9px var(--mono);
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transform: translate(-50%, 10px);
  transition: opacity 0.15s ease, transform 0.15s ease;
}

.toast.visible {
  opacity: 1;
  transform: translate(-50%, 0);
}

/* Responsive */
@media (max-width: 1120px) {
  .site-shell {
    grid-template-columns: 280px minmax(0, 1fr);
  }

  .hero,
  .route-grid,
  .site-footer {
    width: min(100% - 36px, 1040px);
  }

  .part-divider,
  .content-card {
    width: min(var(--content-width), calc(100% - 36px));
  }
}

@media (max-width: 980px) {
  .topbar {
    grid-template-columns: 1fr auto;
  }

  .menu-button {
    display: inline-flex;
  }

  .current-location {
    display: none;
  }

  .site-shell {
    display: block;
  }

  .reading-rail {
    display: none;
  }

  .hero {
    grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
  }
}

@media (max-width: 760px) {
  :root {
    --topbar-height: 48px;
  }

  .topbar {
    padding: 6px 10px;
  }

  .brand span,
  .search-button kbd,
  .ecosystem-link {
    display: none;
  }

  .search-button {
    width: 36px;
    min-width: 36px;
    padding: 0;
    border-radius: 8px;
  }

  .search-button span {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
  }

  .hero {
    grid-template-columns: 1fr;
    gap: 25px;
    width: min(100% - 24px, 680px);
    padding-top: 43px;
  }

  .hero h1 {
    font-size: clamp(34px, 12vw, 52px);
  }

  .route-grid {
    grid-template-columns: 1fr;
    width: min(100% - 24px, 680px);
    margin-bottom: 45px;
  }

  .route-card {
    min-height: 110px;
  }

  .part-divider,
  .content-card {
    width: min(100% - 24px, 680px);
  }

  .part-divider {
    margin-top: 54px;
    padding: 20px 18px;
  }

  .part-count {
    position: static;
    display: inline-flex;
    margin-top: 12px;
  }

  .chapter-meta {
    padding-inline: 14px;
  }

  .section-kicker {
    font-size: 8px;
  }

  .chapter-body {
    padding: 24px 18px 30px;
  }

  .chapter-body h1 {
    font-size: clamp(26px, 9vw, 36px);
  }

  .chapter-body h2 {
    font-size: 19px;
  }

  .chapter-body th,
  .chapter-body td {
    min-width: 104px;
    padding: 9px 10px;
  }

  .chapter-pager {
    grid-template-columns: 1fr;
  }

  .chapter-step.next {
    text-align: left;
  }

  .chapter-step.empty {
    display: none;
  }

  .site-footer {
    display: grid;
    align-items: start;
    width: min(100% - 24px, 680px);
  }

  .site-footer nav {
    justify-content: flex-start;
  }

  .search-overlay {
    place-items: start stretch;
    padding: 10px;
  }

  .search-dialog {
    width: 100%;
    max-height: calc(100dvh - 20px);
  }

  .search-results {
    max-height: calc(100dvh - 250px);
  }

  .search-footer {
    display: none;
  }
}

@media (max-width: 460px) {
  .brand strong {
    font-size: 11px;
  }

  .github-link {
    display: none;
  }

  .hero-actions {
    display: grid;
  }

  .primary-action,
  .secondary-action {
    width: 100%;
  }

  .inventory-grid {
    grid-template-columns: 1fr 1fr;
  }

  .chapter-meta {
    align-items: flex-start;
  }

  .chapter-tools a {
    display: none;
  }

  .search-filters {
    overflow-x: auto;
    flex-wrap: nowrap;
  }

  .search-filters button {
    flex: 0 0 auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}

@media print {
  :root {
    color-scheme: light;
  }

  body {
    background: #fff;
    color: #111;
    font-size: 10pt;
  }

  .topbar,
  .reading-progress,
  .reading-rail,
  .nav-drawer,
  .drawer-backdrop,
  .hero-actions,
  .route-grid,
  .chapter-tools,
  .chapter-pager,
  .back-to-top,
  .toast,
  .search-overlay,
  .site-footer nav {
    display: none !important;
  }

  .site-shell,
  .hero {
    display: block;
  }

  .hero,
  .part-divider,
  .content-card,
  .site-footer {
    width: 100%;
    max-width: none;
  }

  .hero {
    padding: 0 0 22px;
  }

  .inventory-panel {
    margin-top: 20px;
    border-color: #bbb;
    background: #f7f7f7;
    box-shadow: none;
  }

  .content-card,
  .part-divider {
    border-color: #bbb;
    background: #fff;
    box-shadow: none;
    break-inside: avoid-page;
  }

  .chapter-meta,
  .chapter-body blockquote,
  .chapter-body pre,
  .chapter-body .codehilite,
  .chapter-body table {
    background: #f7f7f7;
    border-color: #bbb;
  }

  .chapter-body,
  .chapter-body h1,
  .chapter-body h2,
  .chapter-body h3,
  .chapter-body strong,
  .part-divider h2,
  .hero h1 {
    color: #111;
  }

  .chapter-body a {
    color: #111;
  }

  .chapter-body a[href^="http"]::after {
    content: " (" attr(href) ")";
    font-size: 8pt;
    word-break: break-all;
  }
}

.search-hit {
  animation: handbook-search-hit 1.65s ease;
}

@keyframes handbook-search-hit {
  0%, 100% { background-color: transparent; }
  18%, 58% { background-color: rgba(0, 212, 255, 0.13); }
}