:root {
  color-scheme: dark;
  --bg: #0d1117;
  --panel: #141a23;
  --panel-soft: #1a222d;
  --panel-strong: #202a36;
  --text: #e7edf3;
  --muted: #91a0b2;
  --line: #2b3543;
  --accent: #7aa2f7;
  --accent-strong: #9cc6ff;
  --accent-soft: rgba(122, 162, 247, 0.13);
  --wash: rgba(125, 211, 252, 0.08);
  --code-bg: #0a0f16;
  --code-text: #e7edf3;
  --chip: #1d2733;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.38);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

:root[data-theme="light"] {
  color-scheme: light;
  --bg: #f5f7fa;
  --panel: #ffffff;
  --panel-soft: #edf1f6;
  --panel-strong: #e7edf5;
  --text: #1d2230;
  --muted: #647084;
  --line: #d8dee8;
  --accent: #1f5fbf;
  --accent-strong: #0f4aa2;
  --accent-soft: rgba(31, 95, 191, 0.1);
  --wash: rgba(31, 95, 191, 0.07);
  --code-bg: #111820;
  --code-text: #e7edf2;
  --chip: #eef6f0;
  --shadow: 0 18px 50px rgba(31, 37, 40, 0.13);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

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

button,
input {
  font: inherit;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 12px 22px;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(14px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 300px;
}

#a3c5-logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 58px;
  height: 42px;
  border: 1px solid color-mix(in srgb, var(--accent) 45%, var(--line));
  border-radius: 7px;
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--accent) 16%, transparent), transparent 58%),
    var(--code-bg);
  color: var(--accent);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0;
  box-shadow: 0 0 18px color-mix(in srgb, var(--accent) 12%, transparent);
}

#a3c5-logo sup {
  color: color-mix(in srgb, var(--accent) 72%, var(--text));
  font-size: 0.52em;
  line-height: 0;
}

.brand-copy {
  display: flex;
  flex-direction: column;
}

.brand strong {
  font-size: 15px;
}

.brand span {
  color: var(--muted);
  font-size: 12px;
}

.search-wrap {
  position: relative;
  flex: 1;
  max-width: 760px;
}

.search-icon {
  position: absolute;
  left: 13px;
  top: 50%;
  transform: translateY(-50%);
  width: 17px;
  height: 17px;
  color: var(--muted);
  pointer-events: none;
}

.search-input {
  width: 100%;
  height: 42px;
  padding: 0 14px 0 40px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--text);
  outline: none;
}

.search-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.search-results {
  position: absolute;
  top: 48px;
  left: 0;
  right: 0;
  display: none;
  max-height: min(540px, 70vh);
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.search-results.open {
  display: block;
}

.search-hit {
  display: block;
  padding: 12px 14px;
  border-bottom: 1px solid var(--line);
  color: var(--text);
  text-decoration: none;
  cursor: pointer;
}

.search-hit:last-child {
  border-bottom: 0;
}

a.search-hit.active {
  background: var(--accent-soft);
}

a.search-hit.active strong {
  color: var(--accent-strong);
}

.search-hit strong {
  display: block;
  font-size: 14px;
}

.search-hit span {
  display: block;
  margin-top: 3px;
  color: var(--muted);
  font-size: 12px;
}

.layout {
  display: grid;
  grid-template-columns: 310px minmax(0, 1fr);
  align-items: start;
}

.sidebar {
  position: sticky;
  top: 67px;
  height: calc(100vh - 67px);
  overflow: auto;
  padding: 18px;
  border-right: 1px solid var(--line);
  background: color-mix(in srgb, var(--panel) 80%, var(--bg));
}

.sidebar h2 {
  margin: 0 0 12px;
  font-size: 13px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.tree-chapter {
  margin-bottom: 15px;
}

.tree-chapter > a:not(.tree-file) {
  display: block;
  padding: 7px 8px;
  border-radius: 6px;
  font-weight: 700;
  font-size: 14px;
}

.tree-section {
  margin: 3px 0 8px 12px;
}

.tree-section-title {
  display: block;
  padding: 5px 8px;
  color: var(--muted);
  font-size: 12px;
}

.tree-file {
  display: block;
  padding: 6px 8px 6px 18px;
  border-radius: 6px;
  color: color-mix(in srgb, var(--text) 82%, var(--muted));
  font-size: 12px;
  line-height: 1.3;
}

.tree-single {
  margin: 3px 0 3px 12px;
  padding-left: 8px;
  font-size: 12px;
  font-weight: 400;
}

.tree-file:hover,
.tree-file.active {
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.content {
  min-width: 0;
  padding: 34px clamp(20px, 4vw, 58px) 70px;
}

.content > * {
  width: min(100%, 1080px);
  max-width: 1080px;
  margin-left: auto;
  margin-right: auto;
}

.eyebrow {
  margin: 0 0 10px;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-size: clamp(34px, 5vw, 66px);
  line-height: 1;
  letter-spacing: 0;
}

.lede {
  max-width: 820px;
  margin: 18px 0 0;
  color: rgba(255,255,255,.86);
  font-size: 18px;
  line-height: 1.6;
}

.home-kicker,
.home-intro {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background:
    linear-gradient(135deg, var(--wash), transparent 42%),
    linear-gradient(180deg, color-mix(in srgb, var(--panel) 96%, transparent), var(--panel-soft));
}

.home-kicker {
  margin-bottom: 18px;
}

.home-kicker .resource-links {
  margin: 22px 0 0;
}

.readme-prose {
  margin-top: 0;
}

.readme-prose h2 {
  margin: 12px 0 12px;
  font-size: 20px;
}

.readme-prose a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.resource-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0 0 20px;
}

.resource-btn {
  text-decoration: none !important;
}

.maintainer {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.maintainer a {
  color: var(--accent);
  text-decoration: none;
}

.maintainer a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.section-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 14px;
  margin-top: 28px;
}

.section-grid + .home-intro {
  margin-top: 16px;
}

.chapter-card {
  min-height: 180px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  transition: border-color 0.16s ease, transform 0.16s ease, box-shadow 0.16s ease;
}

.chapter-card:hover {
  transform: translateY(-2px);
  border-color: color-mix(in srgb, var(--accent-strong) 55%, var(--line));
  box-shadow: var(--shadow);
}

.chapter-card h2 {
  margin: 0 0 6px;
  font-size: 20px;
}

.chapter-card p {
  margin: 0 0 14px;
  color: var(--muted);
}

.pill-list {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
}

.pill {
  display: inline-flex;
  padding: 5px 8px;
  border-radius: 999px;
  border: 1px solid transparent;
  background: var(--panel-soft);
  color: color-mix(in srgb, var(--text) 82%, var(--muted));
  font-size: 12px;
  transition: background 0.16s ease, border-color 0.16s ease, color 0.16s ease;
}

.pill:hover {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent);
}

.crumbs {
  margin-bottom: 12px;
  color: var(--muted);
  font-size: 13px;
}

.page-head {
  display: flex;
  justify-content: space-between;
  gap: 22px;
  align-items: end;
  margin-bottom: 22px;
}

.page-title h1 {
  color: var(--text);
  font-size: clamp(30px, 4vw, 40px);
}

.page-title p {
  margin: 10px 0 0;
  color: var(--muted);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: flex-end;
  flex: 0 0 auto;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 30px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--text);
  cursor: pointer;
  font-size: 13px;
}

.btn-icon {
  width: 15px;
  height: 15px;
  flex: none;
}

.btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.theme-toggle {
  margin-left: auto;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  min-height: 36px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--text);
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--accent-strong);
  color: var(--accent-strong);
}

.theme-icon {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

:root[data-theme="dark"] .theme-icon-moon,
:root[data-theme="light"] .theme-icon-sun {
  display: none;
}

.mode-tabs {
  display: inline-flex;
  padding: 2px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-soft);
}

.mode-tabs .btn {
  border: 0;
  background: transparent;
}

.mode-tabs .btn.active {
  background: var(--panel);
  color: var(--accent);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.18);
}

.doc-panel {
  display: block;
}

.doc-panel[hidden] {
  display: none;
}

.prose {
  max-width: 100%;
  font-size: 15px;
  line-height: 1.62;
}

.prose p {
  margin: 0 0 16px;
}

.prose ul {
  margin: 0 0 18px 22px;
  padding: 0;
}

.prose li {
  margin: 6px 0;
}

.inline-code {
  padding: 1px 5px;
  border: 1px solid var(--line);
  border-radius: 5px;
  background: var(--panel-soft);
  color: color-mix(in srgb, var(--accent) 82%, var(--text));
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9em;
}

.katex .math-inline-code {
  padding: 0.02em 0.3em;
  border: 1px solid var(--line);
  border-radius: 0.28em;
  background: var(--panel-soft);
  color: color-mix(in srgb, var(--accent) 82%, var(--text)) !important;
  font-size: 0.82em;
}

.metadata {
  display: grid;
  gap: 7px;
  margin: 14px 0;
}

.meta-row {
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  font-size: 13px;
}

.meta-row strong {
  display: block;
  margin-bottom: 2px;
  color: var(--accent-strong);
}

.meta-row ul {
  margin: 0 0 0 16px;
  padding: 0;
}

.code-section {
  margin: 22px 0;
}

.section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 10px;
}

.section-heading h2 {
  margin: 0;
  font-size: 18px;
}

.small-btn {
  min-height: 28px;
  padding: 0 9px;
  font-size: 12px;
}

pre {
  width: 100%;
  max-width: 100%;
  margin: 0;
  overflow: auto;
  border-radius: 8px;
  background: var(--code-bg);
  color: var(--code-text);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.08);
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 12px;
}

pre code {
  display: block;
  width: max-content;
  min-width: 100%;
  padding: 16px;
  line-height: 1.5;
}

pre code.hljs {
  background: transparent;
}

/* Syntax tokens. The code panel is dark in both themes, so a single bright,
   high-contrast palette serves both (no light-mode overrides needed). */
.tok-keyword {
  color: #82aaff;
  font-weight: 600;
}

.tok-builtin {
  color: #ffa657;
}

.tok-type {
  color: #8be9fd;
}

.tok-function {
  color: #dcdcaa;
}

.tok-string {
  color: #f1fa8c;
}

.tok-char {
  color: #f1fa8c;
}

.tok-number {
  color: #bd93f9;
}

.tok-constant {
  color: #c792ea;
}

.tok-preproc {
  color: #ffb86c;
}

.tok-header {
  color: #d98a8a;
}

.tok-comment {
  color: #6d7da3;
  font-style: italic;
}

.tok-op {
  color: #7d8799;
}

:root[data-theme="light"] #a3c5-logo {
  border-color: #315b95;
  background:
    linear-gradient(135deg, rgba(31, 95, 191, 0.16), transparent 58%),
    #f8fbff;
  color: #113d78;
  box-shadow: 0 0 0 1px rgba(17, 61, 120, 0.08);
}

:root[data-theme="light"] #a3c5-logo sup {
  color: #0b5d3f;
}

.raw-view {
  display: flex;
  align-items: stretch;
  min-height: calc(100vh - 230px);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--code-bg);
  color: var(--code-text);
  overflow: hidden;
}

.raw-gutter {
  margin: 0;
  padding: 16px 12px;
  text-align: right;
  color: var(--muted);
  background: rgba(127, 145, 170, 0.08);
  border-right: 1px solid var(--line);
  box-shadow: none;
  border-radius: 0;
  white-space: pre;
  user-select: none;
  -webkit-user-select: none;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 12px;
  line-height: 1.5;
  width: auto;
}

.raw-pre {
  flex: 1;
  margin: 0;
  background: transparent;
  box-shadow: none;
  border-radius: 0;
}

@media (max-width: 920px) {
  .topbar {
    flex-wrap: wrap;
  }

  .brand {
    min-width: 0;
    width: 100%;
  }

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

  .sidebar {
    position: relative;
    top: 0;
    height: auto;
    max-height: 420px;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .page-head {
    align-items: flex-start;
    flex-direction: column;
  }

  .actions {
    justify-content: flex-start;
  }
}