/*
 * The documentation site's own stylesheet (#159).
 *
 * The header, footer, colours, font and dark mode follow itda.work, the site these pages live
 * under. They are reproduced here rather than linked: itda.work's site.css is a Tailwind build
 * that keeps only the classes its own pages use, so linking it would let an itda.work deploy
 * break this site without a sound.
 *
 * Taken from itda-skills/website at 00f656a1cd95e2f7627d3c5c04fd3f5d2b066592:
 *   templates/base.html, templates/partials/header.html, footer.html, theme_toggle.html
 *     the sticky translucent header, the brand link, the footer row, the theme toggle
 *   static/src/tailwind.css
 *     body colours (gray-50/gray-900, dark slate-900/slate-100), Pretendard, the .prose rules
 *   static/js/head-boot.js, static/js/theme.js
 *     the theme policy: localStorage "theme", "light" by default, html.dark as the switch
 *   static/src/pygments-one-dark.css
 *     code blocks in one-dark in both themes (the token colours come from Pygments itself)
 */

:root {
  --bg: #f9fafb;
  --text: #111827;
  --body: #1f2937;
  --muted: #6b7280;
  --faint: #9ca3af;
  --line: #e5e7eb;
  --line-soft: #f3f4f6;
  --surface: #ffffff;
  --header-bg: rgb(255 255 255 / 0.9);
  --link: #2563eb;
  --link-hover: #1d4ed8;
  --accent-bg: #eff6ff;
  --code-bg: #fefce8;
  --code-text: #854d0e;
  --code-line: rgb(161 98 7 / 0.12);
  --preview-bg: #fef3c7;
  --preview-text: #92400e;
  --problem-bg: #fee2e2;
  --problem-text: #991b1b;
  color-scheme: light;
}

html.dark {
  --bg: #0f172a;
  --text: #f1f5f9;
  --body: #e2e8f0;
  --muted: #94a3b8;
  --faint: #64748b;
  --line: #334155;
  --line-soft: #1e293b;
  --surface: #0f172a;
  --header-bg: rgb(15 23 42 / 0.9);
  --link: #60a5fa;
  --link-hover: #93c5fd;
  --accent-bg: rgb(30 58 138 / 0.25);
  --code-bg: rgb(253 224 71 / 0.08);
  --code-text: #fde68a;
  --code-line: rgb(253 224 71 / 0.18);
  --preview-bg: #451a03;
  --preview-text: #fde68a;
  --problem-bg: #450a0a;
  --problem-text: #fecaca;
  color-scheme: dark;
}

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

html {
  font-family: "Pretendard", system-ui, sans-serif;
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 5rem;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

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

svg {
  display: block;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ── Header (itda.work partials/header.html) ───────────────────── */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--header-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line-soft);
}

.site-header__inner {
  max-width: 80rem;
  margin: 0 auto;
  padding: 0.75rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  min-width: 0;
  white-space: nowrap;
}

.brand__home {
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: -0.025em;
  transition: color 0.15s;
}

.brand__home:hover,
.brand__docs:hover {
  color: var(--link);
}

.brand__sep {
  color: var(--faint);
}

.brand__docs {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--muted);
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color 0.15s;
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.header-link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--muted);
  padding: 0.5rem;
  transition: color 0.15s;
}

.header-link:hover {
  color: var(--text);
}

.icon-button {
  padding: 0.5rem;
  border: 0;
  border-radius: 0.5rem;
  background: transparent;
  color: var(--faint);
  cursor: pointer;
  transition: background-color 0.15s;
}

.icon-button:hover {
  background: var(--line-soft);
}

.icon-button svg {
  width: 1rem;
  height: 1rem;
}

.theme-toggle .icon-sun,
html.dark .theme-toggle .icon-moon {
  display: none;
}

html.dark .theme-toggle .icon-sun {
  display: block;
}

.menu-button {
  display: none;
}

/* ── Banners ─────────────────────────────────────────────────── */

.preview-band {
  background: var(--preview-bg);
  color: var(--preview-text);
  font-size: 0.875rem;
  text-align: center;
  padding: 0.5rem 1rem;
}

.preview-band strong {
  font-weight: 700;
}

/* ── Layout: sidebar, article, table of contents ─────────────── */

.layout {
  flex: 1;
  width: 100%;
  max-width: 80rem;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 16rem minmax(0, 1fr) 13rem;
  gap: 2rem;
  padding: 0 1rem;
}

.layout--no-toc {
  grid-template-columns: 16rem minmax(0, 1fr);
}

.sidebar,
.toc {
  position: sticky;
  top: 4rem;
  align-self: start;
  max-height: calc(100vh - 4rem);
  overflow-y: auto;
  padding: 2rem 0;
  font-size: 0.875rem;
}

.sidebar__section + .sidebar__section {
  margin-top: 1.25rem;
}

.sidebar__heading {
  display: block;
  font-weight: 700;
  color: var(--text);
  padding: 0.25rem 0.5rem;
  border-radius: 0.375rem;
}

.sidebar__level {
  margin: 0.75rem 0 0.25rem;
  padding: 0 0.5rem;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--faint);
}

.sidebar ul {
  list-style: none;
  margin: 0.25rem 0 0;
  padding: 0;
}

.sidebar li a {
  display: block;
  padding: 0.3rem 0.5rem 0.3rem 0.75rem;
  border-left: 2px solid var(--line);
  color: var(--muted);
  transition: color 0.15s;
}

.sidebar a:hover {
  color: var(--text);
}

.sidebar a[aria-current="page"] {
  color: var(--link);
  font-weight: 600;
}

.sidebar li a[aria-current="page"] {
  border-left-color: var(--link);
}

.toc__title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--faint);
  margin: 0 0 0.5rem;
}

.toc ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.toc a {
  display: block;
  padding: 0.25rem 0 0.25rem 0.75rem;
  border-left: 2px solid var(--line);
  color: var(--muted);
  line-height: 1.4;
  transition: color 0.15s;
}

.toc a:hover {
  color: var(--link);
}

.toc .toc__h3 a {
  padding-left: 1.5rem;
  font-size: 0.8125rem;
}

/* The section being read (site.js): the bar and the link colour, as the sidebar marks the page.
   An h3's h2 keeps its colour a step up, without the bar. No weight change: a bolder line can
   wrap and move every entry below it while the reader scrolls. */
.toc a.is-current-parent {
  color: var(--text);
}

.toc a.is-current {
  color: var(--link);
  border-left-color: var(--link);
}

.article {
  min-width: 0;
  padding: 2rem 0 3rem;
}

.page-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0 0 1.5rem;
  font-size: 0.8125rem;
}

.chip {
  display: inline-block;
  padding: 0.15rem 0.6rem;
  border-radius: 999px;
  background: var(--accent-bg);
  color: var(--link);
  font-weight: 600;
}

.page-source {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  font-size: 0.875rem;
}

.page-source a {
  color: var(--muted);
}

.page-source a:hover {
  color: var(--link);
}

.pager {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 2rem;
}

.pager a {
  display: block;
  padding: 0.9rem 1.1rem;
  border: 1px solid var(--line);
  border-radius: 0.75rem;
  background: var(--surface);
  transition: border-color 0.15s;
}

.pager a:hover {
  border-color: var(--link);
}

.pager__next {
  grid-column: 2;
  text-align: right;
}

.pager__label {
  display: block;
  font-size: 0.75rem;
  color: var(--faint);
}

.pager__title {
  display: block;
  font-weight: 600;
  color: var(--link);
  margin: 0.15rem 0;
}

.pager__meta {
  display: block;
  font-size: 0.75rem;
  color: var(--muted);
}

/* ── Prose (itda.work static/src/tailwind.css) ───────────────── */

.prose {
  font-size: 1.0625rem;
  word-break: keep-all;
  overflow-wrap: break-word;
  color: var(--body);
}

.prose h1 {
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.025em;
  color: var(--text);
  margin: 0 0 1rem;
}

.prose h2 {
  font-size: 1.5em;
  font-weight: 700;
  color: var(--text);
  margin: 2em 0 0.65em;
  padding-bottom: 0.35em;
  line-height: 1.3;
  border-bottom: 1px solid var(--line);
}

.prose h3 {
  font-size: 1.25em;
  font-weight: 600;
  color: var(--text);
  margin: 1.6em 0 0.45em;
  line-height: 1.4;
}

.prose h4,
.prose h5,
.prose h6 {
  font-size: 1em;
  font-weight: 600;
  color: var(--text);
  margin: 1.4em 0 0.4em;
}

.heading-anchor {
  margin-left: 0.4em;
  color: var(--faint);
  font-weight: 400;
  opacity: 0;
  transition: opacity 0.15s;
}

.prose :is(h1, h2, h3, h4, h5, h6):hover .heading-anchor,
.heading-anchor:focus {
  opacity: 1;
}

.prose p {
  margin: 1em 0;
  line-height: 1.8;
}

.prose strong {
  font-weight: 650;
  color: var(--text);
}

.prose ul,
.prose ol {
  margin: 1em 0;
  padding-left: 1.75em;
}

.prose li {
  margin: 0.4em 0;
  line-height: 1.75;
}

.prose li::marker {
  color: var(--faint);
}

.prose ol > li::marker {
  font-weight: 600;
}

.prose li > p {
  margin: 0.4em 0;
}

.prose .contains-task-list {
  list-style: none;
  padding-left: 0.25em;
}

.prose img {
  max-width: 100%;
  height: auto;
  border: 1px solid rgb(15 23 42 / 0.1);
  border-radius: 0.5rem;
}

html.dark .prose img {
  border-color: rgb(148 163 184 / 0.2);
}

.prose hr {
  margin: 2.5em 0;
  border: 0;
  border-top: 1px solid var(--line);
}

.prose blockquote {
  margin: 1.25em 0;
  border-left: 3px solid #2563eb;
  padding-left: 1.2em;
  color: var(--muted);
}

.prose a {
  color: var(--link);
}

.prose a:hover {
  text-decoration: underline;
}

.prose :not(pre) > code {
  background: var(--code-bg);
  color: var(--code-text);
  padding: 0.1rem 0.4rem;
  border-radius: 0.3rem;
  border: 1px solid var(--code-line);
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.88em;
  font-weight: 500;
}

.prose a code {
  color: inherit;
}

.prose pre {
  margin: 1.5em 0;
  padding: 1.1rem 1.4rem;
  border-radius: 0.75rem;
  overflow-x: auto;
  font-size: 0.875rem;
  line-height: 1.65;
}

.prose pre code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

.prose table {
  display: block;
  width: 100%;
  overflow-x: auto;
  border-collapse: collapse;
  font-size: 0.875em;
  margin: 1.5em 0;
}

.prose th {
  font-weight: 600;
  text-align: left;
  padding: 0.65em 1em;
  background: var(--line-soft);
  border-bottom: 2px solid var(--line);
  white-space: nowrap;
}

.prose td {
  padding: 0.6em 1em;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.prose kbd {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 0.85em;
  padding: 0.05em 0.35em;
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  border-radius: 0.25rem;
}

/* ── Footer (itda.work partials/footer.html) ─────────────────── */

.site-footer {
  margin-top: 4rem;
  padding: 2.5rem 0;
  border-top: 1px solid var(--line-soft);
  background: var(--surface);
  font-size: 0.875rem;
  color: var(--faint);
}

.site-footer__inner {
  max-width: 80rem;
  margin: 0 auto;
  padding: 0 1rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

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

/* ── Redirect page ───────────────────────────────────────────── */

.moved {
  max-width: 40rem;
  margin: 4rem auto;
  padding: 0 1rem;
}

.moved a {
  color: var(--link);
}

/* ── Narrow screens ──────────────────────────────────────────── */

@media (max-width: 72rem) {
  .layout,
  .layout--no-toc {
    grid-template-columns: 15rem minmax(0, 1fr);
  }

  .toc {
    display: none;
  }
}

@media (max-width: 48rem) {
  .layout,
  .layout--no-toc {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }

  .menu-button {
    display: block;
  }

  .header-link--wide {
    display: none;
  }

  .sidebar {
    display: none;
    position: static;
    max-height: none;
    padding: 1rem 0;
    border-bottom: 1px solid var(--line);
  }

  .sidebar.is-open {
    display: block;
  }

  .article {
    padding-top: 1.5rem;
  }

  .prose h1 {
    font-size: 1.6rem;
  }

  .prose pre {
    padding: 0.9rem 1rem;
    border-radius: 0.5rem;
  }

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

  .pager__next {
    grid-column: 1;
  }
}

@media print {
  .site-header,
  .site-footer,
  .sidebar,
  .toc,
  .preview-band {
    display: none;
  }
}

.highlight { background: #282C34; color: #ABB2BF }
.highlight .c { color: #7F848E } /* Comment */
.highlight .err { color: #ABB2BF } /* Error */
.highlight .esc { color: #ABB2BF } /* Escape */
.highlight .g { color: #ABB2BF } /* Generic */
.highlight .k { color: #C678DD } /* Keyword */
.highlight .l { color: #ABB2BF } /* Literal */
.highlight .n { color: #E06C75 } /* Name */
.highlight .o { color: #56B6C2 } /* Operator */
.highlight .x { color: #ABB2BF } /* Other */
.highlight .p { color: #ABB2BF } /* Punctuation */
.highlight .ch { color: #7F848E } /* Comment.Hashbang */
.highlight .cm { color: #7F848E } /* Comment.Multiline */
.highlight .cp { color: #7F848E } /* Comment.Preproc */
.highlight .cpf { color: #7F848E } /* Comment.PreprocFile */
.highlight .c1 { color: #7F848E } /* Comment.Single */
.highlight .cs { color: #7F848E } /* Comment.Special */
.highlight .gd { color: #ABB2BF } /* Generic.Deleted */
.highlight .ge { color: #ABB2BF } /* Generic.Emph */
.highlight .ges { color: #ABB2BF } /* Generic.EmphStrong */
.highlight .gr { color: #ABB2BF } /* Generic.Error */
.highlight .gh { color: #ABB2BF } /* Generic.Heading */
.highlight .gi { color: #ABB2BF } /* Generic.Inserted */
.highlight .go { color: #ABB2BF } /* Generic.Output */
.highlight .gp { color: #ABB2BF } /* Generic.Prompt */
.highlight .gs { color: #ABB2BF } /* Generic.Strong */
.highlight .gu { color: #ABB2BF } /* Generic.Subheading */
.highlight .gt { color: #ABB2BF } /* Generic.Traceback */
.highlight .kc { color: #E5C07B } /* Keyword.Constant */
.highlight .kd { color: #C678DD } /* Keyword.Declaration */
.highlight .kn { color: #C678DD } /* Keyword.Namespace */
.highlight .kp { color: #C678DD } /* Keyword.Pseudo */
.highlight .kr { color: #C678DD } /* Keyword.Reserved */
.highlight .kt { color: #E5C07B } /* Keyword.Type */
.highlight .ld { color: #ABB2BF } /* Literal.Date */
.highlight .m { color: #D19A66 } /* Literal.Number */
.highlight .s { color: #98C379 } /* Literal.String */
.highlight .na { color: #E06C75 } /* Name.Attribute */
.highlight .nb { color: #E5C07B } /* Name.Builtin */
.highlight .nc { color: #E5C07B } /* Name.Class */
.highlight .no { color: #E06C75 } /* Name.Constant */
.highlight .nd { color: #61AFEF } /* Name.Decorator */
.highlight .ni { color: #E06C75 } /* Name.Entity */
.highlight .ne { color: #E06C75 } /* Name.Exception */
.highlight .nf { color: #61AFEF; font-weight: bold } /* Name.Function */
.highlight .nl { color: #E06C75 } /* Name.Label */
.highlight .nn { color: #E06C75 } /* Name.Namespace */
.highlight .nx { color: #E06C75 } /* Name.Other */
.highlight .py { color: #E06C75 } /* Name.Property */
.highlight .nt { color: #E06C75 } /* Name.Tag */
.highlight .nv { color: #E06C75 } /* Name.Variable */
.highlight .ow { color: #56B6C2 } /* Operator.Word */
.highlight .pm { color: #ABB2BF } /* Punctuation.Marker */
.highlight .w { color: #ABB2BF } /* Text.Whitespace */
.highlight .mb { color: #D19A66 } /* Literal.Number.Bin */
.highlight .mf { color: #D19A66 } /* Literal.Number.Float */
.highlight .mh { color: #D19A66 } /* Literal.Number.Hex */
.highlight .mi { color: #D19A66 } /* Literal.Number.Integer */
.highlight .mo { color: #D19A66 } /* Literal.Number.Oct */
.highlight .sa { color: #98C379 } /* Literal.String.Affix */
.highlight .sb { color: #98C379 } /* Literal.String.Backtick */
.highlight .sc { color: #98C379 } /* Literal.String.Char */
.highlight .dl { color: #98C379 } /* Literal.String.Delimiter */
.highlight .sd { color: #98C379 } /* Literal.String.Doc */
.highlight .s2 { color: #98C379 } /* Literal.String.Double */
.highlight .se { color: #98C379 } /* Literal.String.Escape */
.highlight .sh { color: #98C379 } /* Literal.String.Heredoc */
.highlight .si { color: #98C379 } /* Literal.String.Interpol */
.highlight .sx { color: #98C379 } /* Literal.String.Other */
.highlight .sr { color: #98C379 } /* Literal.String.Regex */
.highlight .s1 { color: #98C379 } /* Literal.String.Single */
.highlight .ss { color: #98C379 } /* Literal.String.Symbol */
.highlight .bp { color: #E5C07B } /* Name.Builtin.Pseudo */
.highlight .fm { color: #56B6C2; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #E06C75 } /* Name.Variable.Class */
.highlight .vg { color: #E06C75 } /* Name.Variable.Global */
.highlight .vi { color: #E06C75 } /* Name.Variable.Instance */
.highlight .vm { color: #E06C75 } /* Name.Variable.Magic */
.highlight .il { color: #D19A66 } /* Literal.Number.Integer.Long */