/* ============================================================
   post.css — styles for writing pages (article + note layouts)
   Loaded ONLY on pages whose layout is `article` or `note`,
   via `_includes/post-head.html`. Does not affect homepage or
   field-notes — which use main.css + field-notes.css respectively.

   Token note: this file uses `--color-*` custom properties; the
   site-wide `main.css` uses unprefixed `--background`, `--foreground`,
   `--muted-foreground`. The two sets do NOT collide. They live in
   different load contexts.

   All selectors are (or will be) prefixed with `.post-root` to
   prevent any accidental bleed even if this stylesheet ever loads
   on a page it shouldn't.

   Sections (filled in subsequent issues):
     :ROOT TOKENS    — done in Issue 1 (this file)
     SHARED          — Issue 4 (prose, page-nav, callouts, footnotes, a11y)
     ARTICLE-ONLY    — Issue 4/5 (frame, cover-band, header grid, TOC, sidenotes)
     NOTE-ONLY       — Issue 6 (single column, centered title, v2-cover, v2-meta)
     ROUGE SHIM      — Issue 7 (map Rouge classes to .tok-* palette)
   ============================================================ */

/* Copy-section-link on H2/H3 in article content.
   The .copyable-heading class is added by JS in _layouts/article.html.
   Heading click → URL with #anchor copies, "Section link copied" toast
   appears. No visual change on the heading itself — cursor:pointer
   (set in JS) signals interactivity, and the toast is the confirmation. */
.post-root .copyable-heading {
  position: relative;
}

/* Reset Chrome's default body margin so the dark footer + page edges
   sit flush against the viewport. Without this, the writing layouts
   render with an 8px white border around the entire page — most
   visible as a white gap below the dark footer. */
html, body {
  margin: 0;
  padding: 0;
}

:root {
  --color-text: #2a2722;
  --color-background: #ffffff;
  --color-text-mid: #6a6760;
  --color-text-faint: #85827c;
  --color-border-mid: #dadada;
  --color-border-light: #ebe9e3;
  --color-rule-strong: #2a2722;

  --color-link: #0066cc;

  --color-note-bg: #e8f4f8;
  --color-note-border: #17a2b8;
  --color-note-fg: #0a5d6b;
  --color-warn-bg: #fff3cd;
  --color-warn-border: #ffc107;
  --color-tip-bg: #f0fff4;
  --color-tip-border: #9ae6b4;
  --color-q-bg: #f8f4ff;
  --color-q-border: #d6bcfa;
  --color-meta-bg: #f5f5f5;
  --color-meta-border: #ddd;

  --color-highlight-pill: #cc3300;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;

  --ease-out: cubic-bezier(0.645, 0.045, 0.355, 1);
  --bdrs: 0.5rem;
  --bdrs-lg: 0.75rem;

  --color-text-on-dark: #fafafa;
  --color-bg-on-dark: #2a2722;
}

/* ============================================================
   SHARED — applies to both article and note layouts
   (Extracted from V1 prototype, all selectors prefixed with
   `.post-root` so they only apply inside writing-layout pages.)
   ============================================================ */

/* ============================================================
   V1 FINAL — article template (heaviest chrome)
   Locked-in decisions from May 2026 design session:
     · Title sans (Helvetica/Inter), Brandur-shaped tracking
     · All links blue (#0066cc)
     · Body sans 16px, Niloofar-leaning
     · Boxed callouts (5 types)
     · GitHub Light code theme
     · Sidenotes on desktop, footnotes on mobile
     · Section number toggle via body[data-section-numbers]
     · Image figures with shadow + italic mid-grey captions
     · Niloofar's exact callout palette
   ============================================================ */
.post-root *, .post-root *::before, .post-root *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* Body-level defaults — applied to the .post-root wrapper so they
   don't leak onto the homepage. The layouts add `class="post-root"`
   to a top-level wrapper div. */
.post-root {
  background: var(--color-background);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  max-width: 100vw;
}
.post-root a { color: inherit; text-decoration: none; }
.post-root ul, .post-root ol { list-style: none; }
.post-root img { display: block; max-width: 100%; }

/* ============================================================
   PAGE NAV — three-zone row, back-link left, version brand right
   ============================================================ */
/* PAGE NAV — three-zone row:
     LEFT:    back arrow (→ /articles)
     CENTER:  "Home" text (→ site root)
     RIGHT:   ✷ v0.1 brand (→ site root, version label)
   Grid lets us pin center to the middle regardless of left/right widths. */
.post-root .page-nav {
  position: relative;
  z-index: 10;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 1.5rem 1rem;
  max-width: 1400px;
  margin: 0 auto;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--color-text);
}
/* THREE-ZONE NAV (Henry pattern):
     LEFT:   ← All Articles (back to article index)
     CENTER: ✷ v0.1 brand with hover-reveal "— Go Home"
     RIGHT:  tagline (empty for now) */

/* LEFT — back arrow + "All Articles" text */
.post-root .page-nav__back-arrow {
  grid-column: 1;
  justify-self: start;
  color: var(--color-text);
  line-height: 1;
  padding: 0.25rem 0.5rem;
  display: inline-flex;
  align-items: baseline;
  gap: 0.5ch;
  transition: opacity 0.15s var(--ease-out);
}
.post-root .page-nav__back-arrow:hover { opacity: 0.6; }
.post-root .page-nav__back-arrow-symbol { font-size: 1.125rem; }
.post-root .page-nav__back-arrow-text {
  font-size: 0.875rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* CENTER — v0.1 brand wrapped in square brackets (self-referential nod
   to the citation system: [1], [2], etc., and now [v0.1]).
   At rest: [ v0.1 ]
   On hover: [ v0.1 — Go Home ] — content grows, brackets stay anchored. */
.post-root .page-nav__brand {
  grid-column: 2;
  justify-self: center;
  color: var(--color-text);
  font-size: 0.875rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  display: inline-flex;
  align-items: baseline;
  white-space: nowrap;
  text-decoration: none;
}
/* The brackets — rendered as pseudo-elements so they stay put while the
   inner content (the flag) animates in. Slight letter-spacing reset on
   the brackets themselves so they sit tight to the text. */
.post-root .page-nav__brand::before,
.post-root .page-nav__brand::after {
  color: var(--color-text-mid);
  letter-spacing: 0;
  margin-inline: 0.4ch;
}
.post-root .page-nav__brand::before { content: '['; }
.post-root .page-nav__brand::after  { content: ']'; }

/* Flag uses max-width animation so the closing bracket slides over
   at rest. Original Henry timing: 0.4s with editorial easing.
   Slower than the default UI transition because this is a "reveal"
   moment, not a state change — it should feel deliberate. */
.post-root .page-nav__brand-flag {
  display: inline-block;
  max-width: 0;
  opacity: 0;
  overflow: hidden;
  white-space: nowrap;
  transform: translateX(-0.5rem);
  transition: max-width 0.4s cubic-bezier(0.645, 0.045, 0.355, 1),
              opacity 0.4s cubic-bezier(0.645, 0.045, 0.355, 1),
              transform 0.4s cubic-bezier(0.645, 0.045, 0.355, 1),
              margin-inline-start 0.4s cubic-bezier(0.645, 0.045, 0.355, 1);
  pointer-events: none;
  margin-inline-start: 0;
}
.post-root .page-nav__brand:hover .page-nav__brand-flag,
.post-root .page-nav__brand:focus-visible .page-nav__brand-flag {
  max-width: 12em;
  opacity: 1;
  transform: translateX(0);
  margin-inline-start: 0.5ch;
}
/* Bracket subtle hover state — they brighten slightly with the rest of
   the brand to signal "this is one connected interactive element". */
.post-root .page-nav__brand:hover::before,
.post-root .page-nav__brand:hover::after {
  color: var(--color-text);
}
@media (prefers-reduced-motion: reduce) {
  .post-root .page-nav__brand-flag { transition-duration: 0s; }
}

/* RIGHT — tagline slot (empty placeholder) */
.post-root .page-nav__tagline {
  grid-column: 3;
  justify-self: end;
}

/* Mobile: just the arrow + centered "v0.1 — Go Home" (always expanded
   since you can't hover on touch — the brand shows its full state). */
@media (max-width: 999px) {
  .post-root .page-nav__back-arrow-text { display: none; }
  /* Force the flag visible always on mobile — same content as desktop hover */
  .post-root .page-nav__brand-flag {
    max-width: 12em;
    opacity: 1;
    transform: translateX(0);
    margin-inline-start: 0.5ch;
    transition: none;
  }
}

/* ============================================================
   ARTICLE FRAME — flex container for header + TOC + cover-band.
   Mobile order (default DOM order): header → mobile-toc → cover
   Desktop reorders to: cover → header (mobile-toc hidden entirely)

   IMPORTANT: children need width:100% otherwise their `margin: auto`
   centers them inside the flex column (shrinks them to 0).
   ============================================================ */
.post-root .article-frame {
  display: flex;
  flex-direction: column;
}
.post-root .article-frame > * { width: 100%; }
/* Mobile order (≤999px):
     1. article-header
     2. cover-band
     3. cover-divider (the thin HR after the cover)
     4. tldr           (plain text summary block)
   TOC card lives inside .article-content prose for both viewports. */
@media (max-width: 999px) {
  .post-root .article-frame .article-header   { order: 1; }
  .post-root .article-frame .cover-band       { order: 2; }
  .post-root .article-frame .cover-divider    { order: 3; }
  .post-root .article-frame .tldr             { order: 4; }
}
@media (min-width: 1000px) {
  /* Desktop: cover FIRST, then header, then TL;DR. cover-divider hidden
     (the article-header bottom border already separates the prose). */
  .post-root .article-frame .cover-band       { order: 1; }
  .post-root .article-frame .article-header   { order: 2; }
  .post-root .article-frame .tldr             { order: 3; }
  .post-root .article-frame .cover-divider    { display: none; }
}

/* ============================================================
   COVER BAND — rounded banner on laptop, square on mobile
   ============================================================ */
.post-root .cover-band {
  max-width: 1400px;
  margin: 1.5rem auto 0;
  padding-inline: 1rem;
}
/* On mobile, the cover sits AFTER the header — so the top margin is
   the breathing room between TOC and cover. Bottom margin ensures the
   rounded corner doesn't visually clip against the divider that follows. */
@media (max-width: 999px) {
  /* Cover sits with breathing room above (so the metadata block doesn't
     crowd it), tight bottom margin so HR is close (Henry pattern). */
  .post-root .cover-band { margin: 2.5rem auto 0; }
}
/* COVER INNER — shared visuals (border, radius, gradient).
   Sizing is handled in separate media-query blocks below so mobile
   and desktop never collide. */
.post-root .cover-band__inner {
  width: 100%;
  max-width: none;
  margin: 0 auto;
  border-radius: var(--bdrs-lg);
  overflow: hidden;
  border: 1.5px solid var(--color-rule-strong);
  background:
    linear-gradient(135deg, #d4cfc4 0%, #e9e6df 50%, #c5beb0 100%);
  position: relative;
}
/* MOBILE sizing only */
@media (max-width: 767px) {
  .post-root .cover-band__inner {
    aspect-ratio: 16 / 9;          /* Henry-like banner on phones */
    height: auto;
  }
}
/* DESKTOP sizing only — restored from original v1 spec */
@media (min-width: 768px) {
  .post-root .cover-band__inner {
    aspect-ratio: auto;
    height: 20rem;                 /* 320px — original v1 banner height */
  }
}
.post-root .cover-band__inner::after {
  content: 'COVER IMAGE  ·  16:9 ON MOBILE  ·  WIDE BANNER ON LAPTOP';
  position: absolute;
  bottom: 1rem;
  left: 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: rgba(42, 39, 34, 0.5);
  text-transform: uppercase;
}
/* When a real image is added (<img class="cover-band__img"> inside .cover-band__inner)
   the img fills the wrapper and the placeholder gradient/label gets hidden. */
.post-root .cover-band__img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.post-root .cover-band__inner:has(.cover-band__img) {
  background: none;
}
.post-root .cover-band__inner:has(.cover-band__img)::after {
  display: none;
}

/* Cover divider — thin HR between cover image and prose on mobile only.
   On desktop the article-header has its own bottom border, so we hide this.
   Audit-fix: dropped max-width:1400px and the conflicting margin-inline
   override that was causing 15-16px horizontal overflow on mobile. */
.post-root .cover-divider {
  border: 0;
  border-top: 1px solid var(--color-border-mid);
  margin: 1rem 0 0;
  width: calc(100% - 2rem);
  margin-inline: 1rem;
  box-sizing: border-box;
}
@media (min-width: 1000px) {
  .post-root .cover-divider { display: none; }
}

/* ============================================================
   ARTICLE HEADER — title, subtitle, authors, meta column
   ============================================================ */
.post-root .article-header {
  max-width: 1400px;
  margin: 4rem auto 3rem;
  padding-inline: 1rem;
  padding-block-end: 1rem;
  border-block-end: 1px solid var(--color-border-mid);
}
/* On mobile, header comes first (before cover). The article-header +
   metadata + cover need to fill the viewport so the HR sits at the
   bottom edge of common mobile screens (iPhone 14/15/16 ~844-852px,
   iPhone Pro Max ~956px). We aim for the HR around y=830-880 absolute. */
@media (max-width: 999px) {
  .post-root .article-header {
    margin-block-start: 4.5rem;     /* extra breathing room from page-nav */
    margin-block-end: 0;
    padding-block-end: 0;
    border-block-end: none;
  }
}
.post-root .article-header__inner {
  display: grid;
  gap: 1rem;
  grid-template-columns: 1fr;
}
@media (min-width: 1000px) {
  .post-root .article-header__inner {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 1rem;
  }
}
.post-root .article-header__mast {
  display: flex;
  flex-direction: column;
}
@media (min-width: 1000px) {
  .post-root .article-header__mast { grid-column: 1 / span 7; }
}
.post-root .article-header__category {
  margin-block-end: 0.875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-mid);
  font-size: 0.75rem;
  font-weight: 600;
}
.post-root .article-header__title {
  font-family: Helvetica, var(--font-sans);
  font-size: 2.5rem;
  font-weight: 400;
  line-height: 1;
  margin-block-end: 1rem;
  letter-spacing: -0.05em;
}
@media (min-width: 1000px) {
  .post-root .article-header__title {
    font-size: 3.75rem;
    letter-spacing: -0.08em;
  }
}
.post-root .article-header__subtitle {
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 1.0625rem;
  line-height: 1.45;
  color: var(--color-text-mid);
  margin-block-end: 1.5rem;
  max-width: 38em;
}
/* Mobile: more breathing room around the title and subtitle so the
   header doesn't feel crumpled when stacked vertically. */
@media (max-width: 999px) {
  .post-root .article-header__category { margin-block-end: 1rem; }
  .post-root .article-header__title { margin-block-end: 1.25rem; }
  .post-root .article-header__subtitle { margin-block-end: 2.25rem; }
}
.post-root .article-header__authors {
  display: flex;
  flex-wrap: wrap;
  gap: 0.875rem 2rem;
  margin-block-end: 1.5rem;
  align-items: baseline;
}
.post-root .article-header__author { display: flex; flex-direction: column; gap: 0.05rem; }
.post-root .article-header__author-name {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
}
.post-root .article-header__author-affil {
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  color: var(--color-text-mid);
}

.post-root .article-header__meta {
  display: grid;
  column-gap: 1.5rem;
  row-gap: 1.25rem;
  grid-template-columns: 1fr 1fr;
  margin-block-end: 2rem;
  text-transform: uppercase;
}
@media (min-width: 1000px) {
  .post-root .article-header__meta {
    grid-column: 9 / span 4;
    grid-row: 1 / span 4;
    grid-template-columns: 1fr 1fr;
    align-content: start;
  }
}
.post-root .article-header__meta dt {
  color: var(--color-text-mid);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-block-end: 0.25rem;
}
.post-root .article-header__meta dd {
  font-size: 0.875rem;
  letter-spacing: 0;
  text-transform: none;
  color: var(--color-text);
}
/* On mobile: hide author block + Last Updated + Status.
   Keep: Written (date), Duration (reading time), Topics.
   Topics moves to the right column of a 2-col grid (Henry pattern). */
@media (max-width: 999px) {
  .post-root .article-header__authors { display: none; }
  .post-root .article-header__meta-row--updated,
  .post-root .article-header__meta-row--status { display: none; }
  .post-root .article-header__meta {
    grid-template-columns: 1fr 1fr;
    grid-template-areas:
      "written topics"
      "duration topics";
    column-gap: 1.5rem;
    row-gap: 1.75rem;             /* breathing room between Written and Duration */
    margin-block-end: 2rem;       /* tighter gap to cover (was 3.5rem — pushed HR off-page) */
  }
  .post-root .article-header__meta-row--written  { grid-area: written; }
  .post-root .article-header__meta-row--duration { grid-area: duration; }
  .post-root .article-header__topics { grid-area: topics; }
  /* Bigger metadata field values on mobile — Henry's read at body size */
  .post-root .article-header__meta dt {
    font-size: 0.6875rem;
    letter-spacing: 0.1em;
  }
  .post-root .article-header__meta dd { font-size: 1rem; }
  .post-root .article-header__topics-list li { font-size: 1rem; }
}

.post-root .article-header__topics {
  /* On desktop, topics spans the full meta width below the other fields */
}
@media (min-width: 1000px) {
  .post-root .article-header__topics { grid-column: 1 / -1; }
}
/* Topics list — plain vertical list everywhere, same as other metadata
   values. No pill chrome — Niloofar pattern. Tanay rejected the pill style. */
.post-root .article-header__topics-list {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
  padding: 0;
  margin: 0;
  list-style: none;
}
.post-root .article-header__topics-list li {
  background: transparent;
  padding: 0;
  border-radius: 0;
  font-size: 0.875rem;
  color: var(--color-text);
  /* Match the inherited text-transform: uppercase from .article-header__meta */
}

/* ============================================================
   MOBILE-TOC — collapsible details/summary card.
   Closed: shows "Table of Contents" + small + icon — IN the rectangle.
   Open: same rectangle expands to show the numbered list — STILL ONE BOX.
   The border lives on .mobile-toc (the wrapper) so it always wraps
   everything inside, including the expanded list (v1 original design).
   ============================================================ */
/* TL;DR — plain text block. Sits between cover (with HR above it) and TOC. */
.post-root .tldr {
  max-width: 1400px;
  margin: 2rem auto 0;
  padding-inline: 1rem;
}
.post-root .tldr__label {
  display: block;
  font-family: var(--font-sans);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-mid);
  font-weight: 500;
  margin-block-end: 0.75rem;
}
.post-root .tldr p {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  margin: 0;
}

/* TOC CARD — boxed, sits inside the prose column on both viewports.
   Restored from original laptop-v1.html: white card, dark border at 60%
   opacity that darkens to 100% on hover, hole-punch dot top-right,
   numbered list with (01)— prefix, grow-from-left link underline. */
.post-root .toc-card {
  background: #fafafa;             /* hair off-white — separates card from pure-white page */
  border: 1.5px solid rgba(42, 39, 34, 0.6);
  border-radius: var(--bdrs);
  /* top, sides, bottom — asymmetric: tighter bottom because the last
     list-item already has line-height leading below its text. */
  padding: 1.125rem 1.5rem 0.875rem;
  margin-block: 0 2.5rem;
  position: relative;
  box-shadow: 0 1px 0 rgba(42, 39, 34, 0.04);
  transition: border-color 0.15s cubic-bezier(0.645, 0.045, 0.355, 1);
}
.post-root .toc-card:hover { border-color: #2a2722; }

.post-root .toc-card__title-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-block-end: 0.625rem;        /* tighter (was 1rem) */
}
.post-root .toc-card__title {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-mid);
  font-weight: 500;
}
/* Hole-punch dot — fill matches page bg so it reads as a hole cut
   through the card. Stays page-color even when border darkens. */
.post-root .toc-card__dot {
  width: 0.75rem;
  height: 0.75rem;
  border: 1.5px solid #2a2722;
  border-radius: 999px;
  background: var(--color-background);
}

/* Force-override the global .article-content ol/li padding+margin rules.
   Without this, the global adds 18px margin + 24px left-padding, which
   made the card feel too padded at the bottom. */
.post-root .article-content .toc-card__list {
  padding: 0;
  margin: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.post-root .article-content .toc-card__list li {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  line-height: 1.5;
  display: flex;
  gap: 0.5ch;
  margin: 0;
  padding-left: 0;
}
.post-root .toc-card__num {
  color: var(--color-text-faint);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.post-root .toc-card__dash { color: var(--color-text-faint); }

/* TOC links — DARK at rest (override the global .article-content blue
   link rule). No resting underline; grow-from-left underline appears
   on hover (Henry's scaleX 0→1 pattern). */
.post-root .article-content .toc-card__link,
.post-root .article-content .toc-card__link:visited,
.post-root .article-content .toc-card__link:hover {
  position: relative;
  z-index: 0;
  color: var(--color-text);
  text-decoration: none;
  border-bottom: none;
}
.post-root .toc-card__link::after {
  content: '';
  position: absolute;
  z-index: -1;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 1px;
  background-color: currentColor;
  transform: scaleX(0);
  transform-origin: 0 0;
  transition: transform 0.2s cubic-bezier(0.645, 0.045, 0.355, 1);
}
.post-root .toc-card__link:hover::after { transform: scaleX(1); }
@media (prefers-reduced-motion: reduce) {
  .post-root .toc-card__link::after { transition: none; }
}
.post-root .mobile-toc__list li {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  line-height: 1.65;
  display: flex;
  gap: 0.5ch;
}
.post-root .mobile-toc__num   { color: var(--color-text-faint); font-variant-numeric: tabular-nums; }
.post-root .mobile-toc__dash  { color: var(--color-text-faint); }
/* Subtle underline on TOC links at rest — they're navigational so
   looking like links matters more here than in prose. (Per Tanay's
   screenshot 47 showing the v1 original style.) */
.post-root .mobile-toc__list a {
  color: var(--color-text);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-decoration-color: var(--color-border-mid);
  text-underline-offset: 0.2em;
  transition: text-decoration-color 0.15s var(--ease-out);
}
.post-root .mobile-toc__list a:hover {
  text-decoration-color: var(--color-text);
}

/* ============================================================
   ARTICLE CONTENT — 12-col grid, prose in cols 4-9
   Sidenotes float in cols 10-12 on desktop.
   ============================================================ */
.post-root .article-content {
  max-width: 1400px;
  margin: 0 auto;
  padding-inline: 1rem;
  padding-block: 2rem 4rem;
}
@media (min-width: 1000px) {
  .post-root .article-content {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 1rem;
  }
  .post-root .article-content > * { grid-column: 4 / span 6; }
  /* Pre + tables stay within prose width so they don't push into the sidenote column.
     Wide-figure can use the extra column 4-10 because figures don't collide with
     sidenotes the same way (figures have margin-block, not inline-block, so they
     don't sit beside sidenotes). */
  .post-root .article-content > pre,
  .post-root .article-content > .table-wrap { grid-column: 4 / span 6; max-width: 100%; min-width: 0; }
  .post-root .article-content > .figure-wide { grid-column: 4 / span 7; }
  .post-root .article-content > .figure-full-bleed { grid-column: 1 / -1; }
  .post-root .article-content > .figure-constrained { grid-column: 5 / span 4; }
  .post-root .article-content > .sidenote,
  .post-root .article-content > .cite-sidenote {
    grid-column: 10 / span 3;
    margin-top: 0;
  }
}

/* ============================================================
   PROSE — headings, paragraphs, inline, lists, code, blockquote
   ============================================================ */
.post-root .article-content { counter-reset: h2-counter; }
.post-root .article-content > h2 {
  font-family: var(--font-sans);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.015em;
  margin-block: 2.5rem 0.75rem;
  color: var(--color-text);
}
.post-root .article-content > h2:not([data-no-number]) {
  counter-increment: h2-counter;
}
.post-root[data-section-numbers="on"] .article-content > h2:not([data-no-number])::before {
  content: counter(h2-counter, decimal-leading-zero);
  display: block;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-text-faint);
  margin-block-end: 0.25rem;
}
.post-root .article-content > h3 {
  font-family: var(--font-sans);
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1.3;
  margin-block: 1.75rem 0.5rem;
  color: var(--color-text);
}

.post-root .article-content > p {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  margin-block-end: 1.125rem;
  color: var(--color-text);
  overflow-wrap: anywhere;
  hyphens: auto;
}
.post-root .article-content strong { font-weight: 600; color: var(--color-text); }
.post-root .article-content em { font-style: italic; }
.post-root .article-content del { text-decoration: line-through; color: var(--color-text-mid); }
.post-root .article-content u {
  text-decoration: underline;
  text-decoration-thickness: 1.5px;
  text-decoration-color: var(--color-text);
  text-underline-offset: 0.25em;
  color: var(--color-text);
}

/* All links blue */
.post-root .article-content a {
  color: var(--color-link);
  text-decoration: none;
}
.post-root .article-content a:hover {
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

.post-root .article-content :not(pre) > code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: #f4f4f4;
  padding: 0.2em 0.4em;
  border-radius: 3px;
  color: var(--color-text);
}
.post-root .article-content mark,
.post-root .article-content .highlight-pill {
  background: transparent;
  font-size: 1.4em;
  font-weight: 700;
  color: var(--color-highlight-pill);
  padding: 0;
}

.post-root .article-content ul,
.post-root .article-content ol {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  padding-left: 1.5rem;
  margin-block: 1.125rem;
  list-style: revert;
}
.post-root .article-content ul { list-style: disc; }
.post-root .article-content ol { list-style: decimal; }
.post-root .article-content li { margin-block-end: 0.3rem; padding-left: 0.25rem; }
.post-root .article-content li > ul,
.post-root .article-content li > ol { margin-block: 0.375rem; }

.post-root .article-content blockquote {
  border-inline-start: 4px solid var(--color-border-mid);
  margin-block: 1.5rem;
  padding-inline-start: 1.25rem;
  color: var(--color-text-mid);
  font-size: 1rem;
  line-height: 1.55;
}
.post-root .article-content blockquote p { margin-block-end: 0.5rem; }
.post-root .article-content blockquote p:last-child { margin-block-end: 0; }

/* Code blocks — GitHub Light theme */
.post-root .article-content pre {
  background: #f6f8fa;
  color: #24292f;
  padding: 1rem 1.25rem;
  border-radius: var(--bdrs);
  border: 1px solid #d0d7de;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.5;
  margin-block: 1.25rem;
}
.post-root .article-content pre code {
  background: transparent; padding: 0; color: inherit;
  font-size: inherit; font-family: inherit; border: 0;
}
.post-root .tok-kw   { color: #cf222e; }
.post-root .tok-fn   { color: #8250df; }
.post-root .tok-str  { color: #0a3069; }
.post-root .tok-num  { color: #0550ae; }
.post-root .tok-com  { color: #6e7781; font-style: italic; }
.post-root .tok-var  { color: #24292f; }
.post-root .tok-op   { color: #24292f; }
.post-root .tok-type { color: #953800; }

/* ============================================================
   FIGURES — image with caption, multiple width variants
   ============================================================ */
.post-root .article-content figure {
  margin-block: 1.75rem;
  text-align: center;
}
.post-root .article-content figure > img,
.post-root .article-content figure > .img-placeholder {
  max-width: 100%;
  border-radius: var(--bdrs);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.14), 0 2px 6px rgba(0, 0, 0, 0.08);
}
.post-root .article-content figcaption {
  font-family: var(--font-sans);
  font-style: italic;
  font-size: 0.8125rem;
  color: var(--color-text-mid);
  margin-top: 0.625rem;
  line-height: 1.45;
  max-width: 38em;
  margin-inline: auto;
}
.post-root .article-content figcaption strong {
  color: var(--color-text);
  font-style: normal;
}
.post-root .img-placeholder {
  background:
    linear-gradient(135deg, #d4cfc4 0%, #e9e6df 50%, #c5beb0 100%);
  color: #4a4540;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  padding: 1rem;
  aspect-ratio: 16 / 9;
}

/* ============================================================
   CALLOUTS — five types, all boxed
   ============================================================ */
.post-root .article-content .callout {
  margin-block: 1.25rem;
  padding: 1rem 1.25rem;
  border-radius: var(--bdrs);
  border: 1px solid;
  font-size: 0.9375rem;
  line-height: 1.55;
}
.post-root .article-content .callout__title {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 0.375rem;
}
.post-root .article-content .callout p:last-child { margin-block-end: 0; }
.post-root .article-content .callout p { margin-block-end: 0.5rem; }
.post-root .article-content .callout--note { background: var(--color-note-bg); border-color: var(--color-note-border); }
.post-root .article-content .callout--note .callout__title { color: var(--color-note-fg); }
.post-root .article-content .callout--warning { background: var(--color-warn-bg); border-color: var(--color-warn-border); }
.post-root .article-content .callout--warning .callout__title { color: #b35400; }
.post-root .article-content .callout--tip { background: var(--color-tip-bg); border-color: var(--color-tip-border); }
.post-root .article-content .callout--tip .callout__title { color: #276749; }
.post-root .article-content .callout--question { background: var(--color-q-bg); border-color: var(--color-q-border); }
.post-root .article-content .callout--question .callout__title { color: #553c9a; }
.post-root .article-content .callout--meta { background: var(--color-meta-bg); border-color: var(--color-meta-border); }
.post-root .article-content .callout--meta .callout__title { color: var(--color-text-mid); }

/* ============================================================
   SIDENOTES — V1 desktop only
   ============================================================ */
.post-root .article-content sup.footnote-ref {
  font-size: 0.7em;
  line-height: 0;
  vertical-align: super;
}
.post-root .article-content sup.footnote-ref a {
  color: var(--color-link);
  font-weight: 600;
  padding: 0 0.1em;
}
/* Sidenote (footnote-only) — Henry's left-rule treatment.
   align-self: start makes the box only as tall as its text. */
.post-root .article-content .sidenote {
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--color-text-mid);
  display: none;
  border-left: 2px solid var(--color-border-mid);
  padding-left: 0.75rem;
  margin-block-end: 0.5rem;
  align-self: start;
}
.post-root .article-content .sidenote__num {
  color: var(--color-link);
  font-weight: 600;
  margin-right: 0.25ch;
}
@media (min-width: 1000px) {
  .post-root .article-content .sidenote { display: block; }
}

/* Cite-sidenote — citations in the right gutter on desktop.
   Distinct from footnote sidenote: blue [N] marker, no left rule,
   reads as a "this is sourced" annotation. Hidden on mobile (full
   bibliography lives in the References block below the prose). */
.post-root .article-content .cite-sidenote {
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--color-text-mid);
  display: none;
  padding-left: 0;
  margin-block-end: 0.5rem;
  align-self: start;
}
.post-root .article-content .cite-sidenote__num {
  color: var(--color-link);
  font-weight: 600;
  margin-right: 0.25ch;
  font-variant-numeric: tabular-nums;
}
.post-root .article-content .cite-sidenote em { font-style: italic; }
.post-root .article-content .cite-sidenote a { color: var(--color-link); text-decoration: none; }
.post-root .article-content .cite-sidenote a:hover { text-decoration: underline; text-underline-offset: 0.2em; }
@media (min-width: 1000px) {
  .post-root .article-content .cite-sidenote {
    display: block;
    grid-column: 10 / span 3;
    margin-top: 0;
  }
}

/* Injected sidenotes (V1 desktop, rendered by sidenotes.html JS).
   Tufte-style: each sidenote is absolutely positioned in the right
   gutter at its anchor's y-coordinate. JS measures and sets `top`.
   Sidenotes don't participate in the 12-col grid; they float above
   it. The grid still pins prose to cols 4-9, leaving cols 10-12 free
   for the sidenotes to overlap into. */
@media (min-width: 1000px) {
  .post-root .article-content {
    position: relative;   /* so sidenote `top` is relative to article box */
  }
  .post-root .article-content .sidenote--injected {
    position: absolute;
    /* Override the grid auto-placement that gives this element an
       implicit `left` based on its source-order grid cell. Explicitly
       set left:auto so width:calc resolves against the container. */
    left: auto;
    right: 0;
    width: calc(25% - 1rem);
    grid-column: auto;
    grid-row: auto;
    top: 0;   /* JS overwrites this */
    margin: 0;
    padding-left: 0.75rem;
    border-left: 2px solid var(--color-border-mid);
    font-family: var(--font-sans);
    font-size: 0.8125rem;
    line-height: 1.5;
    color: var(--color-text-mid);
    transition: top 0.2s var(--ease-out);
  }
  .post-root .article-content .sidenote--injected .sidenote__num {
    color: var(--color-link);
    font-weight: 600;
    margin-right: 0.25ch;
    font-variant-numeric: tabular-nums;
  }
  .post-root .article-content .sidenote--injected p {
    display: inline;
    margin: 0;
  }
  /* Hide the bottom footnotes block on desktop ONLY when sidenotes
     have been injected (the JS adds .sidenotes-active to the article). */
  .post-root .article-content.sidenotes-active ~ .footnotes,
  .post-root .article-content.sidenotes-active .footnotes {
    display: none;
  }
}

/* Footnotes block — always visible at the bottom (V1 mobile, V2,
   and V1 desktop when JS is disabled or sidenotes fail to render). */
.post-root .footnotes {
  grid-column: 4 / span 6 !important;
  margin-block: 3rem 1.5rem;
  padding-block-start: 1.5rem;
  border-block-start: 1px solid var(--color-border-mid);
  font-size: 0.8125rem;
  line-height: 1.55;
  color: var(--color-text-mid);
  font-family: var(--font-sans);
}
.post-root .footnotes ol { padding-left: 1.5rem; margin: 0; list-style: decimal; }
.post-root .footnotes li { margin-block-end: 0.5rem; }
.post-root .footnotes li p { margin-block-end: 0.25rem; }
.post-root .footnotes a.footnote-backref,
.post-root .footnotes a.reversefootnote {
  margin-left: 0.375em;
  color: var(--color-link);
  text-decoration: none;
  font-size: 1rem;
  padding: 0.125rem 0.25rem;
  border-radius: 3px;
  transition: background 0.15s var(--ease-out);
  display: inline-block;
  vertical-align: -0.05em;
}
.post-root .footnotes a.footnote-backref:hover,
.post-root .footnotes a.reversefootnote:hover {
  background: rgba(0, 102, 204, 0.08);
  text-decoration: none;
}
.post-root .article-content sup[role="doc-noteref"] a {
  color: var(--color-link);
  font-weight: 600;
  text-decoration: none;
  padding: 0 0.1em;
}

/* ============================================================
   CITATIONS — distinct from footnotes
   · Inline marker: small [N] in blue, NO sidenote treatment
   · Full bibliography in .references section at the bottom (always shown)
   The citation marker is just a navigation cue. The whole point is to
   stay out of the prose flow — unlike a footnote, the reader doesn't
   need to read the citation while reading the prose.
   ============================================================ */
.post-root .article-content sup.citation-ref {
  font-size: 0.75em;
  line-height: 0;
  vertical-align: super;
  font-weight: 500;
}
.post-root .article-content sup.citation-ref a {
  color: var(--color-link);
  text-decoration: none;
  padding: 0 0.05em;
}
.post-root .article-content sup.citation-ref a::before { content: '['; }
.post-root .article-content sup.citation-ref a::after { content: ']'; }

/* References section — always shown on V1, V2, and mobile. */
.post-root .references {
  grid-column: 4 / span 6 !important;
  margin-block: 3rem 1.5rem;
  padding-block-start: 1.5rem;
  border-block-start: 1px solid var(--color-border-mid);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--color-text-mid);
}
.post-root .references__title {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-mid);
  margin-block-end: 0.875rem;
}
.post-root .references__list {
  list-style: none !important;
  padding: 0;
  margin: 0;
  counter-reset: ref-counter;
}
.post-root .references__entry {
  list-style: none;
  counter-increment: ref-counter;
  margin-block-end: 0.625rem;
  padding-left: 2.25rem;
  text-indent: -2.25rem;
  position: relative;
}
.post-root .references__entry::before {
  content: '[' counter(ref-counter) ']';
  color: var(--color-text-faint);
  font-variant-numeric: tabular-nums;
  margin-right: 0.5ch;
  display: inline-block;
  width: 1.75rem;
}
.post-root .references__entry em { font-style: italic; }
.post-root .references__entry a { font-size: 0.875rem; color: var(--color-link); }
/* Backref arrow on each reference entry — returns to where the citation was made */
.post-root .references__backref {
  margin-left: 0.25em;
  color: var(--color-text-faint) !important;
  text-decoration: none;
}

/* ============================================================
   FULL METADATA CARD — collapsible, closed by default
   Sits between References and Footer. Holds: Authors, Resources,
   Discussion. Slimmer than the original v1 (dropped word count,
   revisions, version, license, translations, BibTeX — useful to
   almost nobody).
   Uses the same details/summary pattern as the TOC for consistency.
   ============================================================ */
.post-root .full-metadata {
  max-width: 1400px;
  margin: 3rem auto 2rem;
  padding-inline: 1rem;
}
/* The card itself — same border + radius as the TOC card.
   Not collapsible; always shows its content. */
.post-root .full-metadata-card {
  background: #fafafa;           /* off-white — separates card from pure-white page */
  border: 1.5px solid rgba(42, 39, 34, 0.6);
  border-radius: var(--bdrs-lg);
  overflow: hidden;
}

/* Card header (label only, no icon since there's no toggle) */
.post-root .full-metadata__header {
  padding: 1rem 1.25rem 0.875rem;
  border-bottom: 1px solid var(--color-border-light);
}
.post-root .full-metadata__label {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-mid);
  font-weight: 500;
}

/* Card body — three sections stacked: Authors, Resources, Discussion */
.post-root .full-metadata__body {
  padding: 1rem 1.5rem 1.5rem;
}
.post-root .full-metadata__section {
  padding-block-start: 1rem;
  margin-block-start: 1rem;
  border-block-start: 1px solid var(--color-border-light);
}
.post-root .full-metadata__section:first-child {
  padding-block-start: 0;
  margin-block-start: 0;
  border-block-start: none;
}
.post-root .full-metadata__section-label {
  font-family: var(--font-sans);
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-mid);
  margin-block-end: 0.625rem;
  display: block;
}
/* The inline link rows inside each section — use the unified blue link color */
.post-root .full-metadata__inline-list {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  line-height: 1.55;
  color: var(--color-text);
}
.post-root .full-metadata__inline-list a {
  color: var(--color-link);
  text-decoration: none;
}
.post-root .full-metadata__inline-list a:hover {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}
.post-root .full-metadata__inline-list .sep {
  color: var(--color-text-faint);
  margin-inline: 0.4ch;
}
/* Resources: each resource type on its own row with a label on the left */
.post-root .full-metadata__resource-row {
  display: grid;
  grid-template-columns: 7rem 1fr;
  gap: 1rem;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  line-height: 1.5;
  margin-block-end: 0.4rem;
}
@media (max-width: 700px) {
  .post-root .full-metadata__resource-row { grid-template-columns: 1fr; gap: 0.25rem; }
}
.post-root .full-metadata__resource-row dt {
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-mid);
  align-self: center;
}
.post-root .full-metadata__resource-row dd { margin: 0; }
.post-root .full-metadata__resource-row dd a {
  color: var(--color-link);
  text-decoration: none;
}
.post-root .full-metadata__resource-row dd a:hover {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}
.post-root .full-metadata__resource-row dd .sep {
  color: var(--color-text-faint);
  margin-inline: 0.4ch;
}

/* ============================================================
   HR + ORNAMENT
   ============================================================ */
.post-root .article-content hr {
  border: 0;
  border-block-start: 1px solid var(--color-border-mid);
  margin-block: 2.5rem;
  max-width: 60%;
  margin-inline: auto;
}
.post-root .article-content .section-divider {
  text-align: center;
  margin-block: 3rem;
  font-size: 1.125rem;
  color: var(--color-text-faint);
  letter-spacing: 1em;
  text-indent: 1em;
}

/* ============================================================
   MATH (KaTeX)
   ============================================================ */
.post-root .article-content .katex-display {
  margin-block: 1.25rem !important;
  overflow-x: auto;
  overflow-y: hidden;
}
.post-root .article-content .katex {
  font-size: 1.05em;
  max-width: 100%;
  display: inline-block;
  overflow-x: auto;
  overflow-y: hidden;
  vertical-align: middle;
}

/* ============================================================
   FOOTER
   ============================================================ */
.post-root .footer {
  background: var(--color-bg-on-dark);
  color: var(--color-text-on-dark);
  padding: 4rem 2rem 3rem;
  margin-block-start: 4rem;
}
.post-root .footer__nav {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  max-width: 1400px;
  margin: 0 auto;
}
@media (min-width: 900px) {
  .post-root .footer__nav {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
  .post-root .footer__section--social { grid-column: span 2; }
}
.post-root .footer__section { display: flex; flex-direction: column; gap: 0.5rem; }
.post-root .footer__meta-title {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-text-faint);
  margin-block-end: 0.5rem;
}
.post-root .footer__link {
  color: var(--color-text-on-dark);
  font-size: 1rem;
  display: inline-block;
  align-self: start;
  position: relative;
}
.post-root .footer__link::after {
  content: ''; position: absolute; bottom: -2px; left: 0;
  width: 100%; height: 1px; background-color: currentColor;
  transform: scaleX(0); transform-origin: 0 0;
  transition: transform 0.2s var(--ease-out);
}
.post-root .footer__link:hover::after { transform: scaleX(1); }

/* Social list with inline SVG icons — hybrid set:
     GitHub + LinkedIn = filled paths (16×16 viewBox, slightly smaller)
     Scholar + Bluesky + Twitter = filled outline (24×24 viewBox)
     Email = stroked outline (24×24)
   All use currentColor so they inherit the white footer text color. */
.post-root .social-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: 0;
  margin: 0;
  list-style: none;
}
.post-root .social-list__list-item {
  display: flex;
  align-items: center;
  gap: 0.75ch;
  font-size: 1rem;
}
.post-root .social-list__icon {
  width: 1.125rem;
  height: 1.125rem;
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-on-dark);
}
.post-root .social-list__icon svg { width: 100%; height: 100%; display: block; }
/* GitHub + LinkedIn have 16×16 viewBoxes — render at 1rem so the
   filled paths don't look heavier than the 24×24 outline icons. */
.post-root .social-list__list-item:nth-child(1) .social-list__icon svg,
.post-root .social-list__list-item:nth-child(2) .social-list__icon svg {
  width: 1rem;
  height: 1rem;
}
.post-root .social-list__link {
  position: relative;
  z-index: 0;
  color: var(--color-text-on-dark);
  text-decoration: none;
  display: inline-block;
}
.post-root .social-list__link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 1px;
  background-color: currentColor;
  transform: scaleX(0);
  transform-origin: 0 0;
  transition: transform 0.2s var(--ease-out);
}
.post-root .social-list__link:hover::after { transform: scaleX(1); }

.post-root .footer__colophon {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  max-width: 1400px;
  margin: 3rem auto 0;
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  color: var(--color-text-faint);
}

/* Section numbers are controlled by body[data-section-numbers]; in
   production that attribute is set by Jekyll from the post frontmatter
   `show_section_numbers: true/false`. No on-page toggle needed. */

@media (prefers-reduced-motion: reduce) {
  .post-root *, .post-root *::before, .post-root *::after { transition: none !important; }
}

/* ============================================================
   KRAMDOWN TOC SHIM — author writes `* TOC\n{:toc}` in markdown,
   Kramdown emits `<ul id="markdown-toc">`. This block skins that
   plain ul into the V1 boxed `.toc-card` look without requiring
   the author to write any HTML.

   To opt out of TOC styling for a post: don't write the `* TOC`
   marker. (Future: per-post `show_toc: false` could swap to a
   plain ul, but the marker IS the toggle.)
   ============================================================ */
.post-root .article-content #markdown-toc {
  background: #fafafa;
  border: 1.5px solid rgba(42, 39, 34, 0.6);
  border-radius: var(--bdrs);
  padding: 1.125rem 1.5rem 0.875rem;
  margin-block: 0 2.5rem;
  list-style: none;
  position: relative;
  box-shadow: 0 1px 0 rgba(42, 39, 34, 0.04);
  transition: border-color 0.15s var(--ease-out);
  counter-reset: toc-counter;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.post-root .article-content #markdown-toc:hover { border-color: #2a2722; }
/* Title row injected via ::before — "Table of Contents" with the hole-punch dot. */
.post-root .article-content #markdown-toc::before {
  content: "Table of Contents";
  font-family: var(--font-sans);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-mid);
  font-weight: 500;
  display: block;
  margin-block-end: 0.625rem;
}
.post-root .article-content #markdown-toc::after {
  content: "";
  position: absolute;
  top: 1.125rem;
  right: 1.5rem;
  width: 0.75rem;
  height: 0.75rem;
  border: 1.5px solid #2a2722;
  border-radius: 999px;
  background: var(--color-background);
}
.post-root .article-content #markdown-toc li {
  counter-increment: toc-counter;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  line-height: 1.5;
  display: flex;
  gap: 0.5ch;
  margin: 0;
  padding-left: 0;
  list-style: none;
}
/* (01) — heading text */
.post-root .article-content #markdown-toc li::before {
  content: "(" counter(toc-counter, decimal-leading-zero) ") —";
  color: var(--color-text-faint);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.post-root .article-content #markdown-toc li a,
.post-root .article-content #markdown-toc li a:visited,
.post-root .article-content #markdown-toc li a:hover {
  position: relative;
  z-index: 0;
  color: var(--color-text);
  text-decoration: none;
  border-bottom: none;
}
.post-root .article-content #markdown-toc li a::after {
  content: '';
  position: absolute;
  z-index: -1;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 1px;
  background-color: var(--color-text);
  transform: scaleX(0);
  transform-origin: 0 0;
  transition: transform 0.2s var(--ease-out);
}
.post-root .article-content #markdown-toc li a:hover::after { transform: scaleX(1); }
/* Hide nested levels — TOC shows H2s only.
   Kramdown emits nested <ul> for H3/H4 children; we collapse them. */
.post-root .article-content #markdown-toc ul {
  display: none;
}

/* ============================================================
   TABLES — Obsidian-style minimal: no header bg, no zebra,
   bordered cells, hover row tint. Applies to both V1 and V2.
   `display: block; overflow-x: auto;` keeps wide tables from
   breaking the prose grid; they get a horizontal scrollbar
   inside the prose column instead.
   ============================================================ */
.post-root .article-content table {
  display: block;
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  border-collapse: collapse;
  margin-block: 1.5rem;
  font-size: 0.875rem;
  font-family: var(--font-sans);
  border: 1px solid var(--color-border-mid);
}
.post-root .article-content thead th {
  background: transparent;
  font-weight: 600;
  color: var(--color-text);
  padding: 0.5rem 0.75rem;
  text-align: left;
  border: 1px solid var(--color-border-mid);
}
.post-root .article-content tbody td {
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--color-border-mid);
  color: var(--color-text);
  vertical-align: top;
}
.post-root .article-content tbody tr:hover { background: rgba(0, 0, 0, 0.02); }
.post-root .article-content tbody td code { font-size: 0.8125rem; }

/* ============================================================
   TASK LISTS — Kramdown emits <input type="checkbox"> inside
   the <li class="task-list-item">. Style the input directly.
   ============================================================ */
.post-root .article-content li.task-list-item {
  list-style: none;
  margin-left: -1.5rem;
  padding-left: 0;
}
.post-root .article-content li.task-list-item input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 0.875rem;
  height: 0.875rem;
  border: 1.5px solid var(--color-border-mid);
  border-radius: 3px;
  margin-right: 0.5rem;
  vertical-align: -0.1rem;
  cursor: default;
  background: transparent;
  flex-shrink: 0;
}
.post-root .article-content li.task-list-item input[type="checkbox"]:checked {
  background: var(--color-text);
  border-color: var(--color-text);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%23fafafa'%3E%3Cpath d='M13.5 4.5L6 12L2.5 8.5L4 7L6 9L12 3Z'/%3E%3C/svg%3E");
  background-size: 80%;
  background-position: center;
  background-repeat: no-repeat;
}

/* ============================================================
   DEFINITION LISTS — <dl><dt><dd>
   ============================================================ */
.post-root .article-content dl {
  margin-block: 1.25rem;
  font-family: var(--font-sans);
}
.post-root .article-content dl dt {
  font-weight: 600;
  color: var(--color-text);
  margin-block-start: 0.625rem;
}
.post-root .article-content dl dt:first-child { margin-block-start: 0; }
.post-root .article-content dl dd {
  margin-block-start: 0.25rem;
  margin-inline-start: 1.5rem;
  color: var(--color-text-mid);
  line-height: 1.55;
}

/* ============================================================
   DETAILS / SUMMARY — boxed, chevron arrow, indented body
   ============================================================ */
.post-root .article-content details {
  margin-block: 1.25rem;
  border: 1px solid var(--color-border-mid);
  border-radius: var(--bdrs);
  padding: 0.625rem 1.125rem;
  background: #fbfaf7;
  transition: padding-block-end 0.15s var(--ease-out);
}
.post-root .article-content details[open] { padding-bottom: 1.125rem; }
.post-root .article-content summary {
  cursor: pointer;
  font-weight: 600;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  color: var(--color-text);
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding-block: 0.25rem;
  user-select: none;
}
.post-root .article-content summary::-webkit-details-marker { display: none; }
.post-root .article-content summary::before {
  content: '';
  display: inline-block;
  width: 0.625rem;
  height: 0.625rem;
  border-right: 1.5px solid var(--color-text-mid);
  border-bottom: 1.5px solid var(--color-text-mid);
  transform: rotate(-45deg);
  transition: transform 0.15s var(--ease-out);
  flex-shrink: 0;
}
.post-root .article-content details[open] summary::before {
  transform: rotate(45deg) translate(-2px, -2px);
}
.post-root .article-content details > *:not(summary) {
  margin-top: 0.625rem;
  margin-inline-start: 1.125rem;
}

/* ============================================================
   MATH — KaTeX display blocks get auto-numbered via CSS counter.
   Inline math (just `$...$`) is left alone — only display ($$ or \[)
   gets a number on the right edge.
   ============================================================ */
.post-root .article-content { counter-reset: eq-counter h2-counter; }
.post-root .article-content .katex-display {
  position: relative;
  counter-increment: eq-counter;
  margin-block: 1.25rem !important;
  overflow-x: auto;
}
.post-root .article-content .katex-display::after {
  content: "(" counter(eq-counter) ")";
  position: absolute;
  right: 0.5rem;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--color-text-faint);
  font-variant-numeric: tabular-nums;
}

/* ============================================================
   PAPER-LIST — grouped paper references aside.
   Background panel, all-caps heading, arrow bullets.
   .link-paper styles single inline paper references too.
   ============================================================ */
.post-root .article-content .paper-list {
  background: #f5f5f5;
  border-radius: var(--bdrs);
  padding: 1rem 1.25rem;
  margin-block: 1.5rem;
}
.post-root .article-content .paper-list > strong {
  display: block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-text-mid);
  margin-bottom: 0.625rem;
  font-weight: 700;
}
.post-root .article-content .paper-list ul {
  list-style: none;
  padding-left: 0;
  margin: 0;
}
.post-root .article-content .paper-list li {
  margin: 0.25rem 0;
  padding-left: 0;
  font-size: 0.9375rem;
}
.post-root .article-content .paper-list li::before {
  content: '→ ';
  color: var(--color-text-faint);
  margin-right: 0.25ch;
}
.post-root .article-content a.link-paper {
  color: var(--color-link);
  text-decoration: none;
}
.post-root .article-content a.link-paper:hover {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}

/* ============================================================
   ASTERISM — manual three-star divider
   ============================================================ */
.post-root .article-content .asterism {
  text-align: center;
  font-size: 1.5rem;
  color: var(--color-text-faint);
  letter-spacing: 0.4em;
  margin-block: 2.5rem;
}

/* ============================================================
   PULL QUOTE — large emphatic display quote with decorative
   open/close quote marks via pseudo-elements.
   ============================================================ */
.post-root .article-content blockquote.pull-quote {
  border: 0;
  padding: 0;
  margin-block: 2.5rem;
  font-size: 1.375rem;
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--color-text);
  text-align: center;
}
.post-root .article-content blockquote.pull-quote::before { content: '"'; opacity: 0.4; }
.post-root .article-content blockquote.pull-quote::after  { content: '"'; opacity: 0.4; }
.post-root .article-content .pull-quote__attribution {
  display: block;
  margin-block-start: 0.625rem;
  font-size: 0.8125rem;
  font-weight: 400;
  color: var(--color-text-mid);
  letter-spacing: 0;
}

/* ============================================================
   EPIGRAPH — small italic attributed quote at section openings
   ============================================================ */
.post-root .article-content .epigraph {
  margin-block: 1.75rem;
  padding-inline-start: 0;
  border: 0;
  font-family: var(--font-sans);
  font-style: italic;
  font-size: 0.9375rem;
  line-height: 1.55;
  color: var(--color-text-mid);
  text-align: left;
}
.post-root .article-content .epigraph__attribution {
  display: block;
  margin-block-start: 0.375rem;
  font-style: normal;
  font-size: 0.8125rem;
  color: var(--color-text-faint);
}

/* ============================================================
   FIGURE-GRID — force a 2-column layout (predictable wrapping).
   3 panels → 2+1, 4 panels → 2+2, etc.
   ============================================================ */
.post-root .article-content .figure-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.625rem;
  text-align: left;
}
.post-root .article-content .figure-grid > img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}
.post-root .article-content .figure-grid > figcaption {
  grid-column: 1 / -1;
  margin-top: 0.5rem;
  text-align: center;
}
@media (max-width: 600px) {
  .post-root .article-content .figure-grid {
    grid-template-columns: 1fr;
  }
}

/* ============================================================
   ABBREVIATION — dotted underline + immediate CSS tooltip
   (the browser's native tooltip on <abbr title> has a long
   delay; this surfaces the expansion faster.)
   ============================================================ */
.post-root .article-content abbr[title] {
  text-decoration: underline dotted;
  text-underline-offset: 0.2em;
  text-decoration-color: var(--color-text-faint);
  cursor: help;
  position: relative;
}
.post-root .article-content abbr[title]:hover::after,
.post-root .article-content abbr[title]:focus::after {
  content: attr(title);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  margin-bottom: 0.375rem;
  padding: 0.25rem 0.5rem;
  background: var(--color-bg-on-dark);
  color: var(--color-text-on-dark);
  font-size: 0.75rem;
  font-style: normal;
  font-weight: 500;
  white-space: nowrap;
  border-radius: 4px;
  pointer-events: none;
  z-index: 100;
}

/* ============================================================
   NOTE-ONLY — V2 layout (lightweight note template, Brandur-clone)
   Scoped to body.layout-note so V1 selectors aren't disturbed.
   ============================================================ */

/* V2 wrapper: single 720px column */
.layout-note .post-root .article {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.5rem 1.5rem 4rem;
}

/* V2 header: just the title, centered. No grid, no subtitle, no authors. */
.layout-note .post-root .article-header {
  margin-block: 3rem 1.5rem;
  text-align: center;
  display: block;            /* override V1's grid */
  padding: 0;
  border: none;
}
.layout-note .post-root .article-header__inner { display: block; padding: 0; }
.layout-note .post-root .article-header__mast { display: block; padding: 0; }

/* V2 title — Helvetica, big, tight tracking (Brandur signature) */
.layout-note .post-root .article-header__title {
  font-family: Helvetica, var(--font-sans);
  font-size: 2rem;
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.06em;
  color: var(--color-text);
  margin: 0;
  text-align: center;
}
@media (min-width: 720px) {
  .layout-note .post-root .article-header__title {
    font-size: 3.125rem;
    letter-spacing: -0.08em;
  }
}

/* V2 cover image — wider than prose (920px max). No forced aspect.
   Sits between header and prose. */
.post-root .v2-cover {
  max-width: 920px;
  margin: 0 auto 2.5rem;
  padding-inline: 1rem;
}
.post-root .v2-cover__inner {
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: var(--bdrs-lg, 0.75rem);
  overflow: hidden;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.10), 0 2px 8px rgba(0, 0, 0, 0.06);
  background: linear-gradient(135deg, #d4cfc4 0%, #e9e6df 50%, #c5beb0 100%);
  position: relative;
}
.post-root .v2-cover__inner:has(.v2-cover__img) {
  aspect-ratio: auto;
  height: auto;
  background: none;
}
.post-root .v2-cover__img {
  display: block;
  max-width: 100%;
  height: auto;
  margin-inline: auto;
}
@media (max-width: 720px) {
  .post-root .v2-cover { padding-inline: 0; }
  .post-root .v2-cover__inner { border-radius: var(--bdrs, 0.5rem); }
}

/* V2 collapsible meta card ("About this post"), sits between footnotes and footer */
.post-root .v2-meta {
  max-width: 720px;
  margin: 3rem auto 2rem;
  padding-inline: 1.5rem;
}
.post-root .v2-meta__card {
  background: #fafafa;
  border: 1.5px solid rgba(42, 39, 34, 0.6);
  border-radius: var(--bdrs, 0.5rem);
  overflow: hidden;
  transition: border-color 0.15s var(--ease-out);
}
.post-root .v2-meta__card:hover { border-color: #2a2722; }
.post-root .v2-meta__summary {
  list-style: none;
  cursor: pointer;
  user-select: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.875rem 1.25rem;
}
.post-root .v2-meta__summary::-webkit-details-marker { display: none; }
.post-root .v2-meta__label {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-mid);
  font-weight: 500;
}
/* + icon → hole-punch dot when open */
.post-root .v2-meta__icon {
  width: 0.875rem;
  height: 0.875rem;
  position: relative;
  flex-shrink: 0;
  transition: all 0.25s var(--ease-out);
}
.post-root .v2-meta__icon::before,
.post-root .v2-meta__icon::after {
  content: '';
  position: absolute;
  background: var(--color-text);
  transition: opacity 0.2s;
}
.post-root .v2-meta__icon::before {
  left: 50%; top: 0; width: 1.5px; height: 100%;
  transform: translateX(-50%);
}
.post-root .v2-meta__icon::after {
  top: 50%; left: 0; height: 1.5px; width: 100%;
  transform: translateY(-50%);
}
.post-root .v2-meta__card[open] .v2-meta__icon {
  border: 1.5px solid var(--color-text);
  border-radius: 999px;
  background: var(--color-background);
}
.post-root .v2-meta__card[open] .v2-meta__icon::before,
.post-root .v2-meta__card[open] .v2-meta__icon::after {
  opacity: 0;
}
.post-root .v2-meta__body {
  padding: 0.25rem 1.25rem 1.125rem;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--color-text-mid);
}
.post-root .v2-meta__row {
  display: grid;
  grid-template-columns: 7rem 1fr;
  gap: 0.5rem 1rem;
  margin-block-end: 0.5rem;
}
.post-root .v2-meta__row dt {
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-mid);
}
.post-root .v2-meta__row dd {
  margin: 0;
  color: var(--color-text);
}
.post-root .v2-meta__row dd a {
  color: var(--color-link);
  text-decoration: none;
}
.post-root .v2-meta__row dd a:hover {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}
@media (max-width: 600px) {
  .post-root .v2-meta__row {
    grid-template-columns: 1fr;
    gap: 0.125rem;
    margin-block-end: 0.75rem;
  }
}

/* V2 uses the SAME `.article-content` wrapper as V1 so all shared
   element styles (callouts, tables, code, footnotes, lists,
   blockquote, figures, etc.) apply automatically.

   V2 only needs to OVERRIDE the V1 12-col grid layout to a single
   column. These rules win on specificity because they include
   `.layout-note`. */
.layout-note .post-root .article-content {
  max-width: 720px;
  padding-inline: 1.5rem;
  padding-block: 0 4rem;
}
@media (min-width: 1000px) {
  .layout-note .post-root .article-content {
    display: block;   /* unset grid */
    grid-template-columns: none;
  }
  .layout-note .post-root .article-content > * {
    grid-column: auto;
    max-width: 100%;
  }
  .layout-note .post-root .article-content > .sidenote,
  .layout-note .post-root .article-content > .cite-sidenote {
    display: none;   /* V2 has no sidenotes */
  }
  .layout-note .post-root .footnotes {
    display: block;   /* V2 always shows footnotes at bottom */
    grid-column: auto !important;
  }
}

/* ============================================================
   ROUGE SHIM — map Kramdown/Rouge's emitted classes to the
   GitHub-Light .tok-* palette already defined above. This way
   markdown code fences (which Kramdown sends to Rouge for
   tokenizing) get the same colors as hand-rolled <span class="tok-*">.

   Lives under .post-root and inside the same `pre code` context
   used by the prose styles.
   ============================================================ */

/* Keywords: import, def, return, if, etc. */
.post-root pre code .k,
.post-root pre code .kd,
.post-root pre code .kn,
.post-root pre code .kr,
.post-root pre code .kc { color: #cf222e; }

/* Function names */
.post-root pre code .nf,
.post-root pre code .nx { color: #8250df; }

/* Strings */
.post-root pre code .s,
.post-root pre code .s1,
.post-root pre code .s2,
.post-root pre code .sb,
.post-root pre code .sd,
.post-root pre code .si,
.post-root pre code .sx { color: #0a3069; }

/* Numbers */
.post-root pre code .mi,
.post-root pre code .mf,
.post-root pre code .mh,
.post-root pre code .il { color: #0550ae; }

/* Comments */
.post-root pre code .c,
.post-root pre code .c1,
.post-root pre code .cm,
.post-root pre code .cp,
.post-root pre code .cs { color: #6e7781; font-style: italic; }

/* Variables / names */
.post-root pre code .n,
.post-root pre code .nv,
.post-root pre code .nb { color: #24292f; }

/* Operators + punctuation */
.post-root pre code .o,
.post-root pre code .p { color: #24292f; }

/* Types / classes */
.post-root pre code .kt,
.post-root pre code .nc { color: #953800; }