/* ============================================================
   neurostatsblog — Main Stylesheet
   Academic serif aesthetic: Spectral + Inter, ink-on-paper light mode,
   warm dark mode. MathJax-ready, code-block-ready.
   ============================================================ */

/* ── 1. Design Tokens ──────────────────────────────────────── */
:root, [data-theme="light"] {
  /* Surfaces — near-white, with subtle warm tint kept on offset surfaces
     (callouts, TOC) for visual hierarchy. */
  --color-bg:              #ffffff;
  --color-surface:         #ffffff;
  --color-surface-2:       #ffffff;
  --color-surface-offset:  #f4f2ed;
  --color-divider:         #ebe8e1;
  --color-border:          #ddd9d1;

  /* Text — near-black, warm-toned */
  --color-text:            #1e1c18;
  --color-text-muted:      #6b6860;
  --color-text-faint:      #b0ada7;
  --color-text-inverse:    #f8f7f3;

  /* Primary accent — deep indigo (cerebral, scientific) */
  --color-primary:         #3a3fbf;
  --color-primary-hover:   #2c2f96;
  --color-primary-active:  #1f206e;
  --color-primary-highlight: #dddff5;

  /* Code accent */
  --color-code-bg:         #f0ede6;
  --color-code-text:       #3a2e1e;
  --color-code-border:     #d9d4cb;

  /* Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.4rem;
  --radius-lg: 0.75rem;

  /* Transitions */
  --transition: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Shadows (warm-tinted) */
  --shadow-sm: 0 1px 3px oklch(0.2 0.01 80 / 0.07);
  --shadow-md: 0 4px 14px oklch(0.2 0.01 80 / 0.09);

  /* Type scale — fluid */
  --text-xs:   clamp(0.7rem,   0.65rem + 0.25vw, 0.5rem);
  --text-sm:   clamp(0.8rem,   0.75rem + 0.3vw,  0.5rem);
  --text-base: clamp(0.875rem, 0.85rem + 0.25vw, 0.5rem);
  --text-lg:   clamp(1rem,     0.9rem  + 0.65vw, 0.5rem);
  --text-xl:   clamp(1.35rem,  1.1rem  + 1.2vw,  0.5rem);
  --text-2xl:  clamp(1.75rem,  1.25rem + 2vw,    0.5rem);
  --text-hero: clamp(2.2rem,   1.3rem  + 3.5vw,  0.5rem);

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --content-narrow: 960px;
  --content-default: 960px;
  --header-height: 60px;

  /* Fonts */
  --font-display: 'Inter', 'Helvetica Neue', Arial, sans-serif;
  --font-body:    'Inter', 'Helvetica Neue', Arial, sans-serif;
  --font-mono:    'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;
}

[data-theme="dark"] {
  --color-bg:              #18160f;
  --color-surface:         #1e1c14;
  --color-surface-2:       #242118;
  --color-surface-offset:  #1b1910;
  --color-divider:         #2e2b22;
  --color-border:          #3a372d;
  --color-text:            #e8e5dc;
  --color-text-muted:      #918e84;
  --color-text-faint:      #5c5a52;
  --color-text-inverse:    #18160f;
  --color-primary:         #8b8ff5;
  --color-primary-hover:   #6a6ee8;
  --color-primary-active:  #5053cc;
  --color-primary-highlight: #2a2b4a;
  --color-code-bg:         #24211a;
  --color-code-text:       #d4cdb8;
  --color-code-border:     #3a3629;
  --shadow-sm: 0 1px 3px oklch(0 0 0 / 0.25);
  --shadow-md: 0 4px 14px oklch(0 0 0 / 0.35);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg:              #18160f;
    --color-surface:         #1e1c14;
    --color-surface-2:       #242118;
    --color-surface-offset:  #1b1910;
    --color-divider:         #2e2b22;
    --color-border:          #3a372d;
    --color-text:            #e8e5dc;
    --color-text-muted:      #918e84;
    --color-text-faint:      #5c5a52;
    --color-text-inverse:    #18160f;
    --color-primary:         #8b8ff5;
    --color-primary-hover:   #6a6ee8;
    --color-primary-active:  #5053cc;
    --color-primary-highlight: #2a2b4a;
    --color-code-bg:         #24211a;
    --color-code-text:       #d4cdb8;
    --color-code-border:     #3a3629;
    --shadow-sm: 0 1px 3px oklch(0 0 0 / 0.25);
    --shadow-md: 0 4px 14px oklch(0 0 0 / 0.35);
  }
}

/* ── 2. Base Reset ─────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  -webkit-text-size-adjust: none;
  text-size-adjust: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + var(--space-4));
  hanging-punctuation: first last;
}

body {
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.65;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color 0.2s ease, color 0.2s ease;
}

main { flex: 1; }

img, picture, video, canvas, svg { display: block; max-width: 100%; height: auto; }
ul[role="list"], ol[role="list"] { list-style: none; }
input, button, textarea, select { font: inherit; color: inherit; }
h1, h2, h3, h4, h5, h6 { text-wrap: balance; line-height: 1.2; }
p, li { text-wrap: pretty; }

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition);
}
a:hover { color: var(--color-primary-hover); }
a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

button { cursor: pointer; background: none; border: none; }

::selection {
  background: var(--color-primary-highlight);
  color: var(--color-text);
}

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

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border-width: 0;
}

/* ── 3. Layout Containers ──────────────────────────────────── */
.container-narrow {
  width: 100%;
  max-width: var(--content-narrow);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

@media (max-width: 640px) {
  .container-narrow { padding-inline: var(--space-4); }
}

/* ── 4. Header ─────────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-height);
  background: color-mix(in oklab, var(--color-bg) 88%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-divider);
  transition: border-color var(--transition), background var(--transition);
}

.header-inner {
  max-width: var(--content-narrow);
  margin-inline: auto;
  padding-inline: var(--space-6);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

@media (max-width: 640px) {
  .header-inner { padding-inline: var(--space-4); }
}

.site-logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--color-text);
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: var(--text-sm);
  letter-spacing: -0.01em;
  transition: opacity var(--transition);
}
.site-logo:hover { opacity: 0.75; color: var(--color-text); }

.site-name {
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.01em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.nav-link {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition);
  font-family: var(--font-body);
  font-weight: 400;
  letter-spacing: 0.01em;
}
.nav-link:hover { color: var(--color-text); }
.nav-link--active { color: var(--color-text); font-weight: 500; }
.nav-link--icon {
  display: flex;
  align-items: center;
  color: var(--color-text-faint);
}
.nav-link--icon:hover { color: var(--color-text-muted); }

/* Theme toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  transition: color var(--transition), background var(--transition);
}
.theme-toggle:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
}

/* Show sun in dark, moon in light */
[data-theme="light"] .icon-sun,
[data-theme="dark"]  .icon-moon { display: none; }
[data-theme="light"] .icon-moon,
[data-theme="dark"]  .icon-sun  { display: block; }

/* Default (system) */
@media (prefers-color-scheme: light) {
  :root:not([data-theme]) .icon-sun  { display: none; }
  :root:not([data-theme]) .icon-moon { display: block; }
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) .icon-moon { display: none; }
  :root:not([data-theme]) .icon-sun  { display: block; }
}

/* ── 5. Footer ─────────────────────────────────────────────── */
.site-footer {
  border-top: 1px solid var(--color-divider);
  padding-block: var(--space-8);
  margin-top: var(--space-20);
}

.footer-inner {
  max-width: var(--content-narrow);
  margin-inline: auto;
  padding-inline: var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  flex-wrap: wrap;
}

@media (max-width: 640px) {
  .footer-inner {
    padding-inline: var(--space-4);
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-4);
  }
}

.footer-left {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.footer-title {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text);
}

.footer-tagline {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  max-width: 42ch;
}

.footer-nav {
  display: flex;
  gap: var(--space-5);
}
.footer-nav a {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition);
}
.footer-nav a:hover { color: var(--color-text); }

/* ── 6. Home Page ──────────────────────────────────────────── */
.page-home { padding-top: var(--space-16); }

.hero {
  padding-block: var(--space-16) var(--space-12);
  border-bottom: 1px solid var(--color-divider);
  margin-bottom: var(--space-12);
}

.hero-logo {
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}

.hero-title {
  font-family: var(--font-display);
  font-size: var(--text-hero);
  font-weight: 300;
  letter-spacing: -0.03em;
  color: var(--color-text);
  margin-bottom: var(--space-3);
  line-height: 1.05;
}

.hero-tagline {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 52ch;
  line-height: 1.6;
  font-weight: 300;
}

/* ── 7. Post List ──────────────────────────────────────────── */
.post-list-section { padding-bottom: var(--space-20); }

.post-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.post-item {
  padding-block: var(--space-8);
  border-bottom: 1px solid var(--color-divider);
}
.post-item:last-child { border-bottom: none; }

.post-meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-2);
  flex-wrap: wrap;
}

.post-date {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  font-family: var(--font-body);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

/* "· Updated <date> (vN)" — sits inline next to .post-date */
.post-updated {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  font-family: var(--font-body);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.post-tags {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.post-doi {
  font-size: var(--text-xs);
  font-family: var(--font-body);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.post-doi a {
  color: var(--color-text-faint);
  text-decoration: none;
  border-bottom: 1px dotted currentColor;
}

.post-doi a:hover,
.post-doi a:focus-visible {
  color: var(--color-primary);
}

.tag {
  display: inline-block;
  font-size: 0.7rem;
  font-family: var(--font-body);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-primary);
  background: var(--color-primary-highlight);
  padding: 0.15em 0.55em;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease;
}

a.tag:hover,
a.tag:focus-visible {
  background: var(--color-primary);
  color: var(--color-bg, #fff);
}

[data-theme="dark"] .tag { opacity: 0.85; }

.post-title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.25;
  margin-bottom: var(--space-3);
}

.post-title a {
  color: var(--color-text);
  text-decoration: none;
  transition: color var(--transition);
}
.post-title a:hover { color: var(--color-primary); }

.post-excerpt {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.65;
  max-width: 62ch;
  margin-bottom: var(--space-3);
  font-weight: 300;
}

.post-read-more {
  font-size: var(--text-sm);
  color: var(--color-primary);
  font-weight: 500;
  text-decoration: none;
  letter-spacing: 0.01em;
  transition: color var(--transition);
}
.post-read-more:hover { color: var(--color-primary-hover); }

.empty-state {
  color: var(--color-text-faint);
  font-style: italic;
  padding-block: var(--space-12);
}

/* ── 8. Post Full ──────────────────────────────────────────── */
.post-full {
  padding-block: var(--space-12) var(--space-20);
}

.post-header {
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-divider);
}

.post-full-title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 400;
  letter-spacing: -0.025em;
  line-height: 1.15;
  margin-top: var(--space-3);
  color: var(--color-text);
}

.post-subtitle {
  margin-top: var(--space-3);
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  font-weight: 300;
  font-style: italic;
  font-family: var(--font-display);
  line-height: 1.4;
}

/* ── 9. Post Body (reading typography) ─────────────────────── */
.post-body {
  font-family: var(--font-display);
  font-size: 1.15rem;
  line-height: 1.7;
  color: var(--color-text);
  font-weight: 400;
  display: flex;
  flex-direction: column;
}

.post-body > .supplementary-notes {
  order: 1;
  margin-top: var(--space-12);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-code-border);
}
.post-body > .supplementary-notes > * + * { margin-top: var(--space-5); }

.post-body > * + * { margin-top: var(--space-5); }
.post-body > :first-child { margin-top: 0; }

.post-body h2 {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
  letter-spacing: -0.02em;
  margin-top: var(--space-12);
  margin-bottom: var(--space-4);
  color: var(--color-text);
}

.post-body h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  letter-spacing: -0.01em;
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
  color: var(--color-text);
}

.post-body h4 {
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-top: var(--space-6);
  margin-bottom: var(--space-2);
  color: var(--color-text-muted);
}

.post-body p,
.post-body li {
  max-width: 100%;
  text-align: justify;
  text-align-last: left;
  hyphens: auto;
  -webkit-hyphens: auto;
}

/* When a paragraph contains a display equation, MathJax renders the math as a
   block-level <mjx-container display="true"> in the middle of the <p>. The
   visual line just before it isn't HTML's last line, so text-align-last
   doesn't fire — leaving it stretched. De-justify the whole paragraph
   instead; the centered equation already breaks the justification rhythm. */
.post-body p:has(mjx-container[display="true"]),
.post-body li:has(mjx-container[display="true"]) {
  text-align: left;
}

.post-body strong { font-weight: 600; }
.post-body em { font-style: italic; }

.post-body a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 0.15em;
  text-decoration-thickness: 1px;
}
.post-body a:hover { text-decoration-thickness: 2px; }

/* Lists */
.post-body ul,
.post-body ol {
  padding-left: var(--space-6);
  max-width: 64ch;
}

.post-body ul { list-style: disc; }
.post-body ol { list-style: decimal; }

.post-body li { margin-top: var(--space-2); }
.post-body li > p { max-width: none; }

/* Footnotes (kramdown renders these as <div class="footnotes"><ol>…</ol></div>) */
.post-body .footnotes {
  margin-top: var(--space-12);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-code-border);
  font-size: 0.9em;
  color: var(--color-text-muted);
}
.post-body .footnotes::before {
  content: "Footnotes";
  display: block;
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-3);
  color: var(--color-text);
}
.post-body .footnotes ol {
  max-width: 100%;
  padding-left: var(--space-5);
}
.post-body .footnotes li { margin-top: var(--space-3); }
.post-body .footnotes li > p { max-width: 100%; }

/* Theorem-like callouts (theorem, lemma, proposition, definition, proof) */
.post-body .callout {
  margin-block: var(--space-6);
  padding: var(--space-4) var(--space-6);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  background: var(--color-primary-highlight);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}
.post-body .callout > :first-child { margin-top: 0; }
.post-body .callout > :last-child  { margin-bottom: 0; }
.post-body .callout p              { max-width: 100%; }

/* The "Theorem (Name)." label rendered as bold inline strong — give it a touch of accent */
.post-body .callout > p:first-child > strong:first-child {
  color: var(--color-primary);
}

/* Variants */
.post-body .callout-lemma {
  border-left-color: var(--color-text-muted);
  background: var(--color-surface-offset);
}
.post-body .callout-lemma > p:first-child > strong:first-child {
  color: var(--color-text);
}

.post-body .callout-definition {
  border-left-color: var(--color-text);
  background: var(--color-surface-offset);
}
.post-body .callout-definition > p:first-child > strong:first-child {
  color: var(--color-text);
}

.post-body .callout-proof {
  background: transparent;
  border-left-color: var(--color-border);
  font-size: 0.95em;
  color: var(--color-text-muted);
}
.post-body .callout-proof > p:first-child > strong:first-child {
  color: var(--color-text-muted);
  font-style: italic;
}

/* Blockquote */
.post-body blockquote {
  border-left: 3px solid var(--color-primary);
  padding-left: var(--space-5);
  margin-left: 0;
  color: var(--color-text-muted);
  font-style: italic;
}

/* Inline code */
.post-body code:not(pre code) {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--color-code-bg);
  color: var(--color-code-text);
  padding: 0.1em 0.4em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-code-border);
}

/* Code blocks */
.post-body pre {
  background: var(--color-code-bg);
  border: 1px solid var(--color-code-border);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  overflow-x: auto;
  margin-block: var(--space-6);
}

.post-body pre code {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.6;
  color: var(--color-code-text);
  background: none;
  border: none;
  padding: 0;
}

/* Math display blocks */
.post-body .MathJax {
  font-size: 1.05em;
}

/* Figures & images */
.post-body figure {
  margin-block: var(--space-8);
}

.post-body figure img {
  border-radius: var(--radius-md);
  border: 1px solid var(--color-divider);
  width: 100%;
}

.post-body figure img.is-zoomable {
  cursor: zoom-in;
  transition: opacity 0.15s ease;
}
.post-body figure img.is-zoomable:hover {
  opacity: 0.85;
}

/* Lightbox overlay (click-to-enlarge for figures) */
.lightbox-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(15, 14, 10, 0.88);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-6);
  cursor: zoom-out;
  opacity: 0;
  transition: opacity 0.18s ease;
}
.lightbox-overlay.is-open { opacity: 1; }

.lightbox-overlay img {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  border-radius: var(--radius-md);
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.5);
}

.post-body figcaption {
  font-size: var(--text-base);
  line-height: 1.55;
  color: var(--color-text);
  font-family: var(--font-body);
  margin-top: var(--space-3);
  font-style: italic;
  text-align: center;
}

/* Tables */
.post-body table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
  margin-block: var(--space-6);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.post-body th {
  background: var(--color-surface-offset);
  font-weight: 600;
  font-family: var(--font-body);
  text-align: left;
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.post-body td {
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-divider);
}

.post-body tr:last-child td { border-bottom: none; }

/* Horizontal rule */
.post-body hr {
  border: none;
  border-top: 1px solid var(--color-divider);
  margin-block: var(--space-10);
}

/* Table of contents (rendered when YAML has `toc: true`; the heading
   above the list has class .no_toc to keep it out of its own TOC). */
.post-body h2.no_toc {
  font-size: 0.85em;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 500;
  margin-top: 0;
  margin-bottom: var(--space-2);
  color: var(--color-text-muted);
}
#markdown-toc {
  margin: 0 0 var(--space-8) 0;
  padding: var(--space-4) var(--space-6);
  background: var(--color-surface-offset);
  border-radius: var(--radius-md);
  font-size: 0.9em;
  list-style: none;
}
#markdown-toc ul {
  list-style: none;
  padding-left: var(--space-5);
  margin-top: var(--space-1);
}
#markdown-toc li {
  margin-top: var(--space-1);
}
#markdown-toc a {
  text-decoration: none;
  color: var(--color-text-muted);
}
#markdown-toc a:hover {
  color: var(--color-primary);
  text-decoration: underline;
}

/* Revision history block (rendered from page.changelog YAML).
   Sits between the post header and the body — bottom border separates
   it from the body content that follows. */
.post-changelog {
  margin-top: var(--space-4);
  margin-bottom: var(--space-5);
  font-size: 0.9em;
  color: var(--color-text-muted);
}
.post-changelog h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  margin-bottom: var(--space-3);
  color: var(--color-text);
}
.post-changelog ul {
  margin: 0;
  padding-left: var(--space-5);
  list-style: disc;
}
.post-changelog li {
  margin-top: var(--space-2);
}

/* ── Post action buttons (cite, view as pdf) ────────────────── */
.post-actions {
  margin-top: var(--space-4);
  margin-bottom: var(--space-8);
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: var(--space-3);
}

/* Let the <details>'s summary + body participate directly in the
   flex layout, so the summary can sit next to the PDF link and the
   bibtex body can wrap to its own row when open. */
.post-citation { display: contents; }
.post-citation > summary { order: 1; }
.post-pdf-link { order: 2; }

.post-citation > summary,
.post-pdf-link {
  display: inline-block;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-primary);
  background: var(--color-primary-highlight);
  padding: 0.45em 0.9em;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease;
  user-select: none;
}

.post-citation > summary::-webkit-details-marker { display: none; }
.post-citation > summary::marker { content: ""; }

.post-citation > summary::before {
  content: "+ ";
  display: inline;
  font-weight: 600;
}
.post-citation[open] > summary::before { content: "− "; }

.post-pdf-link::before {
  content: "↗ ";
  display: inline;
  font-weight: 600;
}

.post-citation > summary:hover,
.post-citation > summary:focus-visible,
.post-pdf-link:hover,
.post-pdf-link:focus-visible {
  background: var(--color-primary);
  color: var(--color-bg, #fff);
}

.post-citation-body {
  position: relative;
  order: 3;
  flex-basis: 100%;
  width: 100%;
}

.post-citation-body pre {
  margin: 0;
  padding: var(--space-4);
  padding-right: 5.5em;
  background: var(--color-surface-offset, #f6f4ef);
  border: 1px solid var(--color-border, #d4cfc6);
  border-radius: var(--radius-sm);
  overflow-x: auto;
  font-size: 0.85em;
  line-height: 1.5;
}

.post-citation-body code {
  background: none;
  padding: 0;
  font-family: var(--font-mono);
  color: var(--color-text);
  white-space: pre;
}

.post-citation-copy {
  position: absolute;
  top: var(--space-2);
  right: var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  background: var(--color-bg, #fff);
  border: 1px solid var(--color-border, #d4cfc6);
  padding: 0.3em 0.7em;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color 0.15s ease, border-color 0.15s ease;
}
.post-citation-copy:hover,
.post-citation-copy:focus-visible {
  color: var(--color-primary);
  border-color: var(--color-primary);
}

/* ── 10. Post Footer / Navigation ──────────────────────────── */
.post-footer {
  margin-top: var(--space-16);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-divider);
}

.post-nav {
  display: flex;
  gap: var(--space-6);
  justify-content: space-between;
  margin-bottom: var(--space-6);
  flex-wrap: wrap;
}

.post-nav-link {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  text-decoration: none;
  max-width: 46%;
}

.post-nav-link--next { margin-left: auto; text-align: right; }

.post-nav-dir {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-family: var(--font-body);
}

.post-nav-title {
  font-family: var(--font-display);
  font-size: var(--text-base);
  color: var(--color-primary);
  line-height: 1.3;
}
.post-nav-link:hover .post-nav-title { color: var(--color-primary-hover); }

.back-to-posts {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition);
}
.back-to-posts:hover { color: var(--color-primary); }

/* ── 11. Static Pages (About) ──────────────────────────────── */
.page-content {
  padding-block: var(--space-12) var(--space-24);
}

.page-header {
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-divider);
}

.page-title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 400;
  letter-spacing: -0.025em;
  color: var(--color-text);
}

.page-subtitle {
  margin-top: var(--space-2);
  font-size: var(--text-base);
  color: var(--color-text-muted);
  font-style: italic;
  font-family: var(--font-display);
}

.page-body {
  font-family: var(--font-display);
  font-size: clamp(1rem, 0.95rem + 0.25vw, 1.15rem);
  line-height: 1.75;
  font-weight: 300;
}

.page-body > * + * { margin-top: var(--space-4); }
.page-body h2 {
  font-size: var(--text-lg);
  font-weight: 500;
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
}
.page-body p { max-width: 66ch; }
.page-body a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 0.15em;
  text-decoration-thickness: 1px;
}
.page-body a:hover { text-decoration-thickness: 2px; }
.page-body ul {
  padding-left: var(--space-6);
  list-style: disc;
  max-width: 62ch;
}
.page-body li { margin-top: var(--space-2); }

/* ── 12. Rouge Syntax Highlighting ─────────────────────────── */
/* Light mode */
.highlight .hll { background: #fffbdd; }
.highlight .c, .highlight .cm, .highlight .c1, .highlight .cs { color: #998; font-style: italic; }
.highlight .err { color: #a61717; background: #e3d2d2; }
.highlight .k, .highlight .kc, .highlight .kd, .highlight .kn, .highlight .kp, .highlight .kr { color: #4a3fbf; font-weight: bold; }
.highlight .kt { color: #458; font-weight: bold; }
.highlight .m, .highlight .mf, .highlight .mh, .highlight .mi, .highlight .mo { color: #099; }
.highlight .s, .highlight .sb, .highlight .sc, .highlight .sd, .highlight .s2, .highlight .sh, .highlight .si, .highlight .sx, .highlight .s1 { color: #d14; }
.highlight .na { color: #008080; }
.highlight .nb { color: #0086b3; }
.highlight .nc { color: #458; font-weight: bold; }
.highlight .no { color: #008080; }
.highlight .nd { color: #3c5d8a; }
.highlight .ni { color: #800080; }
.highlight .ne { color: #900; font-weight: bold; }
.highlight .nf { color: #900; font-weight: bold; }
.highlight .nn { color: #555; }
.highlight .nt { color: #000080; }
.highlight .nv { color: #008080; }
.highlight .o, .highlight .ow { color: #000; font-weight: bold; }
.highlight .p { color: #3a2e1e; }
.highlight .w { color: #bbb; }

[data-theme="dark"] .highlight .k,
[data-theme="dark"] .highlight .kc,
[data-theme="dark"] .highlight .kd,
[data-theme="dark"] .highlight .kn,
[data-theme="dark"] .highlight .kp,
[data-theme="dark"] .highlight .kr { color: #8b8ff5; }
[data-theme="dark"] .highlight .s,
[data-theme="dark"] .highlight .s1,
[data-theme="dark"] .highlight .s2 { color: #e07b7b; }
[data-theme="dark"] .highlight .m,
[data-theme="dark"] .highlight .mi,
[data-theme="dark"] .highlight .mf { color: #5bbfb5; }
[data-theme="dark"] .highlight .nb { color: #6bbee0; }
[data-theme="dark"] .highlight .c,
[data-theme="dark"] .highlight .c1,
[data-theme="dark"] .highlight .cm { color: #6b6860; }
[data-theme="dark"] .highlight .nf { color: #e0b060; }
[data-theme="dark"] .highlight .p { color: #d4cdb8; }
/* ── 13. Post Byline (authors & reviewers) ─────────────────── */
.post-byline {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-divider);
  font-size: var(--text-xs);
  font-family: var(--font-body);
  color: var(--color-text-muted);
  line-height: 1.5;
}

.byline-label {
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-faint);
  margin-right: 0.3em;
}

.byline-item {
  display: inline;
}

.byline-separator {
  color: var(--color-text-faint);
  padding-inline: var(--space-1);
}

.byline-link {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s ease, color 0.15s ease;
}

.byline-link:hover,
.byline-link:focus-visible {
  color: var(--color-primary);
  border-bottom-color: currentColor;
}

/* Fix inline MathJax SVG forcing line breaks */
mjx-container[jax="SVG"] svg {
  display: inline !important;
  vertical-align: middle;
}

mjx-container[jax="SVG"][display="true"] svg {
  display: block !important;
  margin: auto;
}

/* ── 14. Search ────────────────────────────────────────────── */

/* Header search — input on wide viewports, icon on narrow. */
.header-search {
  position: relative;
  display: flex;
  align-items: center;
  margin-inline: var(--space-2);
}

.header-search-icon {
  position: absolute;
  left: 0.55rem;
  color: var(--color-text-faint);
  pointer-events: none;
}

.header-search-input {
  width: 11rem;
  padding: 0.35rem 0.6rem 0.35rem 1.85rem;
  font: inherit;
  font-size: var(--text-sm);
  color: var(--color-text);
  background: color-mix(in oklab, var(--color-bg) 60%, var(--color-divider) 40%);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  outline: none;
  transition: border-color var(--transition), background var(--transition), width var(--transition);
}

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

.header-search-input:focus {
  border-color: var(--color-primary);
  background: var(--color-bg);
}

/* Below the breakpoint, hide the input and show the icon link. */
.nav-link--search-icon { display: none; }

@media (max-width: 768px) {
  .header-search { display: none; }
  .nav-link--search-icon { display: flex; }
}

/* Search page */
.search-page {
  padding-block: var(--space-8) var(--space-12);
}

.search-header {
  margin-bottom: var(--space-6);
}

.search-title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 400;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-4);
}

.search-form {
  margin: 0;
}

.search-input {
  width: 100%;
  padding: 0.75rem 1rem;
  font: inherit;
  font-size: var(--text-md);
  color: var(--color-text);
  background: var(--color-bg);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

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

.search-input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px color-mix(in oklab, var(--color-primary) 18%, transparent);
}

.search-status {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-family: var(--font-body);
  margin-bottom: var(--space-4);
  min-height: 1.5em;
}

.search-results {
  margin: 0;
  padding: 0;
  list-style: none;
}

/* Pagefind wraps matches in <mark> inside the excerpt. */
.search-results mark,
.post-excerpt mark {
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  padding: 0 0.15em;
  border-radius: 2px;
  font-weight: 500;
}