/* ────────────────────────────────────────────────────────────────
   site.css — shared design system for the notes blog.
   Linear-clean, Geist sans + mono, electric-blue single accent.
   Light / dark / auto via [data-theme] on <html>; defaults to auto.
   ──────────────────────────────────────────────────────────────── */

/* Tokens --------------------------------------------------------- */
:root {
  --bg:            #fafafa;
  --bg-elevated:   #ffffff;
  --bg-subtle:     #f4f4f5;
  --fg:            #09090b;
  --fg-muted:      #52525b;
  --fg-subtle:     #a1a1aa;
  --border:        #e4e4e7;
  --border-strong: #d4d4d8;
  --accent:        #2563eb;
  --accent-hover:  #1d4ed8;
  --accent-fg:     #ffffff;
  --accent-tint:   rgba(37, 99, 235, 0.10);
  --code-bg:       #f4f4f5;
  --code-border:   #e4e4e7;
  --selection:     rgba(37, 99, 235, 0.20);

  --font-sans:  "Geist", -apple-system, BlinkMacSystemFont, "Segoe UI",
                "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
                "Helvetica Neue", Arial, sans-serif;
  --font-mono:  "Geist Mono", ui-monospace, SFMono-Regular, "JetBrains Mono",
                "Cascadia Code", Consolas, "Courier New", monospace;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  --ease-out:  cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast:  120ms;
  --dur-base:  200ms;
  --dur-slow:  360ms;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg:            #0a0a0b;
    --bg-elevated:   #111114;
    --bg-subtle:     #18181b;
    --fg:            #fafafa;
    --fg-muted:      #a1a1aa;
    --fg-subtle:     #71717a;
    --border:        #27272a;
    --border-strong: #3f3f46;
    --accent:        #60a5fa;
    --accent-hover:  #93c5fd;
    --accent-fg:     #0a0a0b;
    --accent-tint:   rgba(96, 165, 250, 0.14);
    --code-bg:       #18181b;
    --code-border:   #27272a;
    --selection:     rgba(96, 165, 250, 0.24);
    --shadow-sm:     0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md:     0 4px 16px rgba(0, 0, 0, 0.5);
    --shadow-lg:     0 12px 40px rgba(0, 0, 0, 0.6);
  }
}

:root[data-theme="dark"] {
  --bg:            #0a0a0b;
  --bg-elevated:   #111114;
  --bg-subtle:     #18181b;
  --fg:            #fafafa;
  --fg-muted:      #a1a1aa;
  --fg-subtle:     #71717a;
  --border:        #27272a;
  --border-strong: #3f3f46;
  --accent:        #60a5fa;
  --accent-hover:  #93c5fd;
  --accent-fg:     #0a0a0b;
  --accent-tint:   rgba(96, 165, 250, 0.14);
  --code-bg:       #18181b;
  --code-border:   #27272a;
  --selection:     rgba(96, 165, 250, 0.24);
  --shadow-sm:     0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md:     0 4px 16px rgba(0, 0, 0, 0.5);
  --shadow-lg:     0 12px 40px rgba(0, 0, 0, 0.6);
}

:root[data-theme="light"] {
  --bg:            #fafafa;
  --bg-elevated:   #ffffff;
  --bg-subtle:     #f4f4f5;
  --fg:            #09090b;
  --fg-muted:      #52525b;
  --fg-subtle:     #a1a1aa;
  --border:        #e4e4e7;
  --border-strong: #d4d4d8;
  --accent:        #2563eb;
  --accent-hover:  #1d4ed8;
  --accent-fg:     #ffffff;
  --accent-tint:   rgba(37, 99, 235, 0.10);
  --code-bg:       #f4f4f5;
  --code-border:   #e4e4e7;
  --selection:     rgba(37, 99, 235, 0.20);
}

/* Reset ---------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

::selection { background: var(--selection); }

html {
  -webkit-text-size-adjust: 100%;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.65;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "cv11", "ss03", "ss04";
  letter-spacing: -0.005em;
}

/* Fixed top-right / top-left controls --------------------------- */
#theme-toggle,
#lang-toggle,
#post-lang-toggle,
#post-home-link {
  position: fixed;
  top: 16px;
  z-index: 100;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 11px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0;
  background: var(--bg-elevated);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  text-decoration: none;
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease-out),
              background var(--dur-fast) var(--ease-out),
              color var(--dur-fast) var(--ease-out);
}

#theme-toggle:hover,
#lang-toggle:hover,
#post-lang-toggle:hover,
#post-home-link:hover {
  border-color: var(--accent);
  color: var(--accent);
}

#theme-toggle      { right: 16px; }
#lang-toggle       { right: 96px; }
#post-lang-toggle  { right: 16px; }
#post-home-link    { left: 16px; }

/* Landing layout ------------------------------------------------- */
.wrap {
  max-width: 720px;
  margin: 0 auto;
  padding: 88px 24px 96px;
}

/* Header --------------------------------------------------------- */
.site-header {
  margin-bottom: 56px;
}

.site-header h1 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 600;
  letter-spacing: -0.035em;
  line-height: 1.05;
  margin: 0 0 10px;
}

.site-header .tagline {
  color: var(--fg-muted);
  font-size: 15px;
  margin: 0;
  letter-spacing: -0.005em;
}

/* Filter bar ---------------------------------------------------- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin: 0 0 40px;
  padding: 0;
  background: transparent;
  border: none;
  border-radius: 0;
}

.filter-bar .label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  color: var(--fg-subtle);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-right: 6px;
}

.tag-chip {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 500;
  color: var(--fg-muted);
  background: var(--bg-subtle);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  user-select: none;
  transition: all var(--dur-fast) var(--ease-out);
  letter-spacing: -0.005em;
}

.tag-chip:hover {
  color: var(--fg);
  background: var(--bg-elevated);
  border-color: var(--border);
}

.tag-chip.active {
  background: var(--fg);
  color: var(--bg);
  border-color: var(--fg);
}

/* Posts ---------------------------------------------------------- */
#post-list { display: flex; flex-direction: column; gap: 4px; }

.post {
  display: block;
  position: relative;
  padding: 20px 0;
  border-top: 1px solid var(--border);
  text-decoration: none;
  color: var(--fg);
  transition: background var(--dur-fast) var(--ease-out);
  border-radius: 0;
}

.post:last-of-type {
  border-bottom: 1px solid var(--border);
}

.post:hover {
  background: linear-gradient(
    90deg,
    var(--accent-tint) 0%,
    transparent 80%
  );
}

.post:hover .post-title {
  color: var(--accent);
}

.post.hidden { display: none; }

.post-title {
  font-size: 16px;
  font-weight: 600;
  margin: 0 0 6px;
  letter-spacing: -0.015em;
  transition: color var(--dur-fast) var(--ease-out);
}

.post-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--fg-subtle);
  margin-bottom: 6px;
  letter-spacing: 0;
  font-variant-numeric: tabular-nums;
}

.post-summary {
  font-size: 14px;
  color: var(--fg-muted);
  line-height: 1.6;
  margin: 0 0 10px;
  max-width: 65ch;
}

/* On hover-capable devices, hide summaries by default and reveal on hover.
   Touch devices keep summaries visible (no hover state). */
@media (hover: hover) and (pointer: fine) {
  .post .post-summary {
    max-height: 0;
    margin: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height var(--dur-base) var(--ease-out),
                opacity   var(--dur-base) var(--ease-out),
                margin    var(--dur-base) var(--ease-out);
  }
  .post:hover .post-summary,
  .post:focus-visible .post-summary {
    max-height: 240px;
    margin: 0 0 10px;
    opacity: 1;
  }
}

.post-tags { display: flex; gap: 6px; flex-wrap: wrap; }
.post-tag {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  color: var(--fg-subtle);
  padding: 1px 6px;
  background: var(--bg-subtle);
  border-radius: var(--radius-sm);
  letter-spacing: 0;
}

/* Series grouping ----------------------------------------------- */
.series-group {
  margin: 12px 0;
  padding: 18px 20px 6px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  position: relative;
}

.series-group::before {
  content: "";
  position: absolute;
  left: -1px; top: -1px; bottom: -1px;
  width: 3px;
  background: var(--accent);
  border-radius: var(--radius-md) 0 0 var(--radius-md);
}

.series-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 6px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.series-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--fg);
  letter-spacing: -0.005em;
}

.series-count {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--fg-subtle);
  font-variant-numeric: tabular-nums;
}

.series-group .post {
  border-top: 1px solid var(--border);
  padding: 14px 0;
}

/* Collapsible series: hide non-latest posts when group is collapsed.
   The series-header acts as the toggle when collapsible. */
.series-header[role="button"] {
  cursor: pointer;
  user-select: none;
}
.series-group[data-collapsed="true"] .post.hidden-collapsed {
  display: none;
}
.series-toggle {
  display: inline-block;
  margin-left: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--fg-muted);
  transition: transform var(--dur-fast) var(--ease-out);
}
.series-group:not([data-collapsed="true"]) .series-toggle {
  transform: rotate(180deg);
}
.series-header[role="button"]:hover .series-toggle,
.series-header[role="button"]:hover .series-count {
  color: var(--accent);
}

.series-group .post:first-of-type {
  border-top: none;
}

.series-group .post:last-of-type {
  border-bottom: none;
}

.series-badge {
  display: inline-block;
  padding: 0 5px;
  margin-right: 6px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  background: var(--accent);
  color: var(--accent-fg);
  border-radius: 3px;
  vertical-align: 1px;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
}

/* Empty / loading states ---------------------------------------- */
.empty {
  color: var(--fg-subtle);
  text-align: center;
  padding: 64px 0;
  font-size: 13px;
  font-style: normal;
  font-family: var(--font-mono);
}

/* Footer --------------------------------------------------------- */
footer {
  margin-top: 80px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--fg-subtle);
  letter-spacing: 0;
}

footer a { color: var(--fg-muted); text-decoration: none; }
footer a:hover { color: var(--accent); }

/* ──────────────────────────────────────────────────────────────
   POST PAGE STYLES — applied to articles in posts/*.html
   ────────────────────────────────────────────────────────────── */

.layout {
  display: flex;
  align-items: flex-start;
  min-height: 100vh;
}

aside.toc {
  position: sticky;
  top: 0;
  flex: 0 0 300px;
  width: 300px;
  height: 100vh;
  overflow-y: auto;
  padding: 32px 20px 32px 24px;
  border-right: 1px solid var(--border);
  background: var(--bg-subtle);
  font-size: 13px;
}

aside.toc .toc-title {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--fg-subtle);
  text-transform: uppercase;
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

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

aside.toc li { margin: 1px 0; }

aside.toc ul ul {
  padding-left: 12px;
  border-left: 1px solid var(--border);
  margin: 2px 0 2px 5px;
}

aside.toc a {
  display: block;
  padding: 4px 8px;
  color: var(--fg-muted);
  text-decoration: none;
  border-radius: var(--radius-sm);
  line-height: 1.4;
  font-size: 12.5px;
  transition: all var(--dur-fast) var(--ease-out);
}

aside.toc a:hover {
  background: var(--bg-elevated);
  color: var(--fg);
}

aside.toc a.active {
  background: var(--accent-tint);
  color: var(--accent);
  font-weight: 600;
}

main.content {
  flex: 1 1 auto;
  min-width: 0;
  max-width: 800px;
  padding: 64px 64px 96px;
  margin: 0 auto;
}

main.content h1,
main.content h2,
main.content h3,
main.content h4 {
  scroll-margin-top: 24px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--fg);
}

main.content h1 {
  font-size: clamp(1.85rem, 3vw, 2.4rem);
  line-height: 1.15;
  margin: 0 0 16px;
  padding-bottom: 0.3em;
  border-bottom: 1px solid var(--border);
  letter-spacing: -0.03em;
}

main.content h2 {
  font-size: 1.5rem;
  margin-top: 2.4em;
  margin-bottom: 0.6em;
  padding-bottom: 0.25em;
  border-bottom: 1px solid var(--border);
  letter-spacing: -0.022em;
}

main.content h3 {
  font-size: 1.15rem;
  margin-top: 2em;
  margin-bottom: 0.5em;
}

main.content h4 {
  font-size: 1rem;
  margin-top: 1.6em;
  margin-bottom: 0.4em;
}

main.content p,
main.content li {
  font-size: 15px;
  line-height: 1.72;
  color: var(--fg);
}

main.content p { margin: 0.9em 0; }

main.content a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur-fast) var(--ease-out);
}

main.content a:hover {
  border-bottom-color: var(--accent);
}

main.content a.headerlink {
  color: var(--fg-subtle);
  border: none;
  margin-left: 8px;
  opacity: 0;
  transition: opacity var(--dur-fast) var(--ease-out);
  font-weight: 400;
}

main.content h1:hover .headerlink,
main.content h2:hover .headerlink,
main.content h3:hover .headerlink,
main.content h4:hover .headerlink {
  opacity: 1;
}

main.content code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: var(--radius-sm);
  padding: 1px 5px;
  letter-spacing: 0;
}

main.content pre {
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.55;
}

main.content pre code {
  background: transparent;
  border: none;
  padding: 0;
  font-size: inherit;
}

main.content blockquote {
  border-left: 3px solid var(--accent);
  background: var(--bg-subtle);
  padding: 10px 16px;
  margin: 1.2em 0;
  color: var(--fg-muted);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

main.content blockquote p { margin: 0.4em 0; }

main.content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2em 0;
  font-size: 14px;
}

main.content table th,
main.content table td {
  text-align: left;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
}

main.content table th {
  font-weight: 600;
  color: var(--fg-muted);
  background: var(--bg-subtle);
  border-bottom-color: var(--border-strong);
}

main.content table tr:hover { background: var(--bg-subtle); }

main.content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2.4em 0;
}

main.content img,
main.content svg {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-md);
}

main.content figure {
  margin: 1.6em 0;
}

main.content figcaption {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--fg-subtle);
  text-align: center;
  margin-top: 8px;
  letter-spacing: 0;
}

/* Mobile --------------------------------------------------------- */
@media (max-width: 900px) {
  .layout { flex-direction: column; }
  aside.toc {
    position: static;
    width: 100%;
    flex: none;
    height: auto;
    max-height: none;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding: 16px 20px;
  }
  main.content {
    padding: 32px 20px 64px;
    max-width: 100%;
  }
  #post-home-link { left: 12px; top: 12px; padding: 6px 9px; font-size: 11px; }
  #post-lang-toggle { right: 12px; top: 12px; padding: 6px 9px; font-size: 11px; }
}

@media (max-width: 600px) {
  .wrap { padding: 64px 18px 64px; }
  .site-header h1 { font-size: 1.85rem; }
  #theme-toggle, #lang-toggle {
    padding: 6px 9px;
    font-size: 11px;
    top: 12px;
  }
  #theme-toggle { right: 12px; }
  #lang-toggle  { right: 84px; }
}

/* Static nav.toc sidebar (onetrans-style) ----------------------- */
nav.toc {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 280px;
  overflow-y: auto;
  overflow-x: hidden;
  background: var(--bg-subtle);
  border-right: 1px solid var(--border);
  padding: 56px 16px 24px 20px;
  font-size: 12.5px;
  line-height: 1.5;
  box-sizing: border-box;
  z-index: 90;
}

nav.toc strong {
  display: block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-subtle);
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

nav.toc ul {
  list-style: none;
  margin: 4px 0;
  padding-left: 14px;
}
nav.toc > div > ul,
nav.toc > ul { padding-left: 0; }

nav.toc li { margin: 1px 0; }

nav.toc a {
  display: block;
  padding: 4px 8px;
  color: var(--fg-muted);
  text-decoration: none;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  line-height: 1.4;
  transition: all var(--dur-fast) var(--ease-out);
}
nav.toc a:hover {
  background: var(--bg-elevated);
  color: var(--fg);
}
nav.toc > div > ul > li > a,
nav.toc > ul > li > a {
  font-weight: 600;
  color: var(--fg);
}
nav.toc ul ul a {
  font-size: 11.5px;
  color: var(--fg-subtle);
}
nav.toc a.active,
nav.toc ul ul a.active {
  background: var(--accent-tint);
  border-left-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}
nav.toc code {
  font-family: var(--font-mono);
  font-size: 11px;
  background: transparent;
  border: none;
  padding: 0;
}

/* Push main.content right when a nav.toc sidebar is present.
   Uses :has() (Safari 15.4+, Chrome 105+, Firefox 121+). */
body:has(nav.toc) main.content {
  max-width: 920px;
  margin-left: 300px;
  margin-right: auto;
  padding: 56px 40px 96px;
}

@media (max-width: 900px) {
  nav.toc {
    position: static;
    width: auto;
    bottom: auto;
    max-height: 280px;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding: 24px 20px;
  }
  body:has(nav.toc) main.content {
    margin-left: auto;
    padding: 24px 20px 64px;
  }
}

/* Dynamic TOC sidebar (#toc, used by gemm-ai-style scripts) ----- */
#toc {
  position: fixed;
  top: 64px;
  left: 16px;
  width: 248px;
  max-height: calc(100vh - 96px);
  overflow-y: auto;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 14px 14px 16px;
  font-size: 12.5px;
  line-height: 1.5;
  box-shadow: var(--shadow-md);
  z-index: 90;
}
#toc.collapsed {
  width: 40px;
  padding: 10px 8px;
  overflow: hidden;
}
#toc.collapsed > *:not(#toc-toggle) { display: none; }

#toc-toggle {
  position: absolute;
  top: 6px;
  right: 6px;
  border: none;
  background: transparent;
  cursor: pointer;
  color: var(--fg-subtle);
  font-size: 14px;
  padding: 4px 6px;
  line-height: 1;
  border-radius: var(--radius-sm);
  transition: color var(--dur-fast) var(--ease-out),
              background var(--dur-fast) var(--ease-out);
}
#toc-toggle:hover { background: var(--bg-subtle); color: var(--fg); }

#toc h4 {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  color: var(--fg-subtle);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding-right: 28px;
  border-bottom: 1px solid var(--border);
  padding-bottom: 8px;
}

#toc ul { list-style: none; padding: 0; margin: 0; }
#toc li { margin: 1px 0; }
#toc a {
  display: block;
  color: var(--fg-muted);
  text-decoration: none;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  line-height: 1.4;
  word-break: break-word;
  transition: all var(--dur-fast) var(--ease-out);
}
#toc a:hover {
  background: var(--bg-subtle);
  color: var(--fg);
}
#toc a.active {
  background: var(--accent-tint);
  border-left-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}
#toc li.lvl-3 > a {
  padding-left: 18px;
  font-size: 11.5px;
  color: var(--fg-subtle);
}
#toc li.lvl-3 > a.active { color: var(--accent); }

@media (max-width: 1180px) {
  #toc { display: none; }
}

/* Callouts / asides / examples (post content) ------------------- */
main.content .callout,
main.content .aside,
main.content .example,
main.content .practice {
  margin: 1.2em 0;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  border-left-width: 3px;
  font-size: 14px;
  line-height: 1.65;
  background: var(--bg-subtle);
}

main.content .callout {
  border-left-color: var(--accent);
}

main.content .callout.note {
  border-left-color: var(--accent);
}

main.content .callout.warn,
main.content .practice {
  border-left-color: #d97706;
  background: rgba(217, 119, 6, 0.06);
}

main.content .example {
  border-left-color: var(--accent);
  background: var(--accent-tint);
}

main.content .aside {
  border-left-color: var(--fg-subtle);
  background: var(--bg-subtle);
}

main.content .callout .label,
main.content .aside .label,
main.content .example .label,
main.content .practice .label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--fg-subtle);
  margin-bottom: 6px;
}

main.content .example .label { color: var(--accent); }
main.content .practice .label { color: #d97706; }

main.content .callout > p:first-child,
main.content .aside > p:first-child,
main.content .example > p:first-child,
main.content .practice > p:first-child { margin-top: 0; }

main.content .callout > p:last-child,
main.content .aside > p:last-child,
main.content .example > p:last-child,
main.content .practice > p:last-child { margin-bottom: 0; }

main.content .figure-caption {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--fg-subtle);
  text-align: center;
  margin: 4px 0 12px;
  letter-spacing: 0;
}

main.content .small {
  font-size: 13px;
  color: var(--fg-muted);
}

main.content .tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  padding: 1px 6px;
  background: var(--accent-tint);
  color: var(--accent);
  border-radius: var(--radius-sm);
  vertical-align: middle;
  letter-spacing: 0;
}

main.content .toc-back-to-top {
  display: block;
  margin-top: 20px;
  font-family: var(--font-mono);
  color: var(--fg-subtle);
  font-size: 11.5px;
  text-decoration: none;
}
main.content .toc-back-to-top:hover { color: var(--accent); }

/* Inline syntax color tokens (legacy .kw / .cm) ----------------- */
main.content .kw { color: #c026d3; font-weight: 500; }
main.content .cm { color: var(--fg-subtle); font-style: italic; }
:root[data-theme="dark"] main.content .kw,
:root:not([data-theme="light"]) main.content .kw { color: #f0abfc; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) main.content .kw { color: #f0abfc; }
}

/* Pygments .codehilite — single neutral scheme that adapts ----- */
main.content .codehilite { background: transparent; }
main.content .codehilite .c,
main.content .codehilite .ch,
main.content .codehilite .cm,
main.content .codehilite .c1,
main.content .codehilite .cs,
main.content .codehilite .cp,
main.content .codehilite .cpf { color: var(--fg-subtle); font-style: italic; }
main.content .codehilite .k,
main.content .codehilite .kc,
main.content .codehilite .kd,
main.content .codehilite .kn,
main.content .codehilite .kp,
main.content .codehilite .kr,
main.content .codehilite .kt { color: #c026d3; font-weight: 500; }
main.content .codehilite .o, main.content .codehilite .ow { color: var(--fg-muted); }
main.content .codehilite .s, main.content .codehilite .s1, main.content .codehilite .s2,
main.content .codehilite .sa, main.content .codehilite .sb, main.content .codehilite .sc,
main.content .codehilite .sd, main.content .codehilite .se, main.content .codehilite .sh,
main.content .codehilite .si, main.content .codehilite .sx, main.content .codehilite .sr,
main.content .codehilite .ss, main.content .codehilite .dl { color: #16a34a; }
main.content .codehilite .m, main.content .codehilite .mb, main.content .codehilite .mf,
main.content .codehilite .mh, main.content .codehilite .mi, main.content .codehilite .mo,
main.content .codehilite .il { color: var(--accent); }
main.content .codehilite .nb, main.content .codehilite .bp { color: #0891b2; }
main.content .codehilite .nc, main.content .codehilite .nn, main.content .codehilite .nf,
main.content .codehilite .nv, main.content .codehilite .vc, main.content .codehilite .vg,
main.content .codehilite .vi, main.content .codehilite .vm, main.content .codehilite .fm { color: var(--fg); }
main.content .codehilite .nd { color: #c026d3; }
main.content .codehilite .nt, main.content .codehilite .na { color: #c026d3; }
main.content .codehilite .ne, main.content .codehilite .gr, main.content .codehilite .err { color: #dc2626; }
main.content .codehilite .gi { color: #16a34a; }
main.content .codehilite .gd { color: #dc2626; }
main.content .codehilite .gh, main.content .codehilite .gp, main.content .codehilite .gu { color: var(--accent); font-weight: 600; }
main.content .codehilite .gs { font-weight: 600; }
main.content .codehilite .ge { font-style: italic; }
main.content .codehilite .w { color: var(--fg-subtle); }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) main.content .codehilite .k,
  :root:not([data-theme="light"]) main.content .codehilite .kc,
  :root:not([data-theme="light"]) main.content .codehilite .kd,
  :root:not([data-theme="light"]) main.content .codehilite .kn,
  :root:not([data-theme="light"]) main.content .codehilite .kp,
  :root:not([data-theme="light"]) main.content .codehilite .kr,
  :root:not([data-theme="light"]) main.content .codehilite .kt,
  :root:not([data-theme="light"]) main.content .codehilite .nd,
  :root:not([data-theme="light"]) main.content .codehilite .nt,
  :root:not([data-theme="light"]) main.content .codehilite .na { color: #e879f9; }
  :root:not([data-theme="light"]) main.content .codehilite .s,
  :root:not([data-theme="light"]) main.content .codehilite .s1,
  :root:not([data-theme="light"]) main.content .codehilite .s2,
  :root:not([data-theme="light"]) main.content .codehilite .sa,
  :root:not([data-theme="light"]) main.content .codehilite .sb,
  :root:not([data-theme="light"]) main.content .codehilite .sc,
  :root:not([data-theme="light"]) main.content .codehilite .sd,
  :root:not([data-theme="light"]) main.content .codehilite .se,
  :root:not([data-theme="light"]) main.content .codehilite .sh,
  :root:not([data-theme="light"]) main.content .codehilite .si,
  :root:not([data-theme="light"]) main.content .codehilite .sx,
  :root:not([data-theme="light"]) main.content .codehilite .sr,
  :root:not([data-theme="light"]) main.content .codehilite .ss,
  :root:not([data-theme="light"]) main.content .codehilite .dl,
  :root:not([data-theme="light"]) main.content .codehilite .gi { color: #4ade80; }
  :root:not([data-theme="light"]) main.content .codehilite .nb,
  :root:not([data-theme="light"]) main.content .codehilite .bp { color: #67e8f9; }
  :root:not([data-theme="light"]) main.content .codehilite .ne,
  :root:not([data-theme="light"]) main.content .codehilite .gr,
  :root:not([data-theme="light"]) main.content .codehilite .err,
  :root:not([data-theme="light"]) main.content .codehilite .gd { color: #f87171; }
}
:root[data-theme="dark"] main.content .codehilite .k,
:root[data-theme="dark"] main.content .codehilite .kc,
:root[data-theme="dark"] main.content .codehilite .kd,
:root[data-theme="dark"] main.content .codehilite .kn,
:root[data-theme="dark"] main.content .codehilite .kp,
:root[data-theme="dark"] main.content .codehilite .kr,
:root[data-theme="dark"] main.content .codehilite .kt,
:root[data-theme="dark"] main.content .codehilite .nd,
:root[data-theme="dark"] main.content .codehilite .nt,
:root[data-theme="dark"] main.content .codehilite .na { color: #e879f9; }
:root[data-theme="dark"] main.content .codehilite .s,
:root[data-theme="dark"] main.content .codehilite .s1,
:root[data-theme="dark"] main.content .codehilite .s2,
:root[data-theme="dark"] main.content .codehilite .sa,
:root[data-theme="dark"] main.content .codehilite .sb,
:root[data-theme="dark"] main.content .codehilite .sc,
:root[data-theme="dark"] main.content .codehilite .sd,
:root[data-theme="dark"] main.content .codehilite .se,
:root[data-theme="dark"] main.content .codehilite .sh,
:root[data-theme="dark"] main.content .codehilite .si,
:root[data-theme="dark"] main.content .codehilite .sx,
:root[data-theme="dark"] main.content .codehilite .sr,
:root[data-theme="dark"] main.content .codehilite .ss,
:root[data-theme="dark"] main.content .codehilite .dl,
:root[data-theme="dark"] main.content .codehilite .gi { color: #4ade80; }
:root[data-theme="dark"] main.content .codehilite .nb,
:root[data-theme="dark"] main.content .codehilite .bp { color: #67e8f9; }
:root[data-theme="dark"] main.content .codehilite .ne,
:root[data-theme="dark"] main.content .codehilite .gr,
:root[data-theme="dark"] main.content .codehilite .err,
:root[data-theme="dark"] main.content .codehilite .gd { color: #f87171; }

/* Reduced motion ------------------------------------------------- */
@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;
  }
}

/* Scroll reveal -------------------------------------------------- */
.reveal {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity var(--dur-slow) var(--ease-out),
              transform var(--dur-slow) var(--ease-out);
}
.reveal.shown {
  opacity: 1;
  transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; }
}
