/* =================================================================
 * POP 핸드북 — Editorial Brutalism
 * Instrument Serif × Pretendard × JetBrains Mono
 * Paper cream + ink + plotter blue + vermillion
 * ================================================================= */

/* ---------- fonts ---------- */
@import url('https://fonts.googleapis.com/css2?family=Instrument+Serif:ital@0;1&family=JetBrains+Mono:wght@400;500;700&display=swap');
@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/variable/pretendardvariable.min.css');

/* ---------- tokens ---------- */
:root {
  --paper: #F4F3EE;
  --paper-deep: #EAE8DF;
  --card: #FBFAF4;
  --ink: #15140F;
  --ink-soft: #42403A;
  --mute: #7C766C;
  --rule: #D9D4C7;
  --rule-soft: #E8E3D5;

  /* Pompeian red — iron-oxide pigment used in archival printed matter */
  --accent: #8C3A20;
  --accent-deep: #6E2D17;
  --accent-tint: #F0E1D7;

  /* muted forest, used sparingly for callouts / underlines */
  --alert: #3F5C45;
  --alert-tint: #DEE5DD;

  --code-bg: #1B1814;
  --code-fg: #EBE5D4;
  --code-mute: #7C7567;
  --code-accent: #D9A862;
  --code-string: #8FA77A;
  --code-keyword: #C76A4E;
  --code-comment: #685F50;

  --font-display: "Instrument Serif", "Times New Roman", serif;
  --font-sans: "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Menlo, Consolas, monospace;

  --maxw: 1320px;
  --col: 760px;

  color-scheme: light;
}

:root[data-theme="dark"] {
  --paper: #15140F;
  --paper-deep: #0B0A07;
  --card: #1D1B16;
  --ink: #EFECE2;
  --ink-soft: #B7B1A2;
  --mute: #76705F;
  --rule: #2A2720;
  --rule-soft: #1B1813;

  --accent: #D67555;
  --accent-deep: #EFA98A;
  --accent-tint: #3A1C12;

  --alert: #7DA084;
  --alert-tint: #1C2A20;

  --code-bg: #0A0907;
  --code-fg: #EFECE2;
  color-scheme: dark;
}

/* ---------- reset / base ---------- */
* { box-sizing: border-box; }
html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.005em;
  font-feature-settings: "ss01", "ss02", "tnum";
}

/* paper grain (subtle noise via radial gradients on body — no images) */
body::before {
  content: '';
  position: fixed; inset: 0; pointer-events: none; z-index: -1;
  background-image:
    radial-gradient(circle at 7% 19%, var(--rule-soft) 0.5px, transparent 1px),
    radial-gradient(circle at 53% 67%, var(--rule-soft) 0.5px, transparent 1px),
    radial-gradient(circle at 89% 41%, var(--rule-soft) 0.5px, transparent 1px),
    radial-gradient(circle at 23% 83%, var(--rule-soft) 0.5px, transparent 1px);
  background-size: 73px 89px, 113px 67px, 47px 59px, 91px 71px;
  opacity: 0.35;
  mix-blend-mode: multiply;
}
:root[data-theme="dark"] body::before { mix-blend-mode: screen; opacity: 0.15; }

a {
  color: var(--accent);
  text-decoration: none;
  text-underline-offset: 4px;
  text-decoration-thickness: 1px;
}
a:hover { text-decoration: underline; }

::selection { background: var(--accent); color: var(--paper); }

/* ---------- top nav ---------- */
.topnav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--paper) 90%, transparent);
  backdrop-filter: blur(12px) saturate(180%);
  -webkit-backdrop-filter: blur(12px) saturate(180%);
  border-bottom: 1px solid var(--rule);
}
.topnav-inner {
  max-width: var(--maxw); margin: 0 auto;
  padding: 14px 32px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 16px;
}
.brand {
  display: inline-flex; align-items: baseline; gap: 12px;
  color: var(--ink);
}
.brand:hover { text-decoration: none; }
.brand-mark {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 24px;
  color: var(--accent);
  line-height: 1;
  letter-spacing: -0.01em;
}
.brand-title {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.brand-title small {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 0.14em;
  color: var(--mute);
  text-transform: uppercase;
  margin-top: 2px;
}
.topnav-center {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mute);
  text-align: center;
}
.topnav-actions {
  display: flex; gap: 4px; justify-content: flex-end; align-items: center;
}
.nav-link {
  display: inline-block;
  padding: 8px 12px;
  font-size: 12px;
  font-family: var(--font-mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-soft);
  border-radius: 0;
  position: relative;
}
.nav-link::after {
  content: ''; position: absolute; left: 12px; right: 12px; bottom: 4px;
  height: 1px; background: var(--accent);
  transform: scaleX(0); transform-origin: left; transition: transform .25s;
}
.nav-link:hover { color: var(--accent); text-decoration: none; }
.nav-link:hover::after { transform: scaleX(1); }
.theme-btn {
  width: 36px; height: 36px;
  background: transparent;
  color: var(--ink-soft);
  border: 1px solid var(--rule);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 13px;
  display: grid; place-items: center;
  transition: border-color .2s, color .2s, background .2s;
}
.theme-btn:hover { border-color: var(--ink); color: var(--ink); }
.theme-btn .theme-label { line-height: 1; }

/* ---------- containers ---------- */
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 32px; }

/* ---------- LANDING : hero ---------- */
.cover {
  max-width: var(--maxw); margin: 0 auto;
  padding: 96px 32px 64px;
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 64px;
  border-bottom: 1px solid var(--rule);
}
.cover-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--mute);
  margin: 0 0 32px;
  display: inline-flex; align-items: center; gap: 14px;
}
.cover-eyebrow::before {
  content: ''; display: inline-block;
  width: 36px; height: 1px; background: var(--accent);
}
.cover-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(56px, 8vw, 124px);
  line-height: 0.92;
  letter-spacing: -0.025em;
  margin: 0;
  color: var(--ink);
}
.cover-title em {
  font-style: italic;
  color: var(--accent);
}
.cover-korean {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: clamp(22px, 2.4vw, 32px);
  line-height: 1.45;
  letter-spacing: -0.025em;
  margin: 48px 0 0;
  color: var(--ink);
  max-width: 580px;
}
.cover-korean .accent { color: var(--accent); font-weight: 700; }
.cover-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mute);
  margin-top: 56px;
  display: flex; gap: 28px; flex-wrap: wrap;
}
.cover-meta span { display: inline-flex; gap: 8px; }
.cover-meta b {
  font-weight: 600; color: var(--ink-soft);
  letter-spacing: 0.06em;
}

.cover-side {
  border-left: 1px solid var(--rule);
  padding: 12px 0 12px 40px;
  align-self: stretch;
  display: flex; flex-direction: column; gap: 28px;
}
.cover-side-block { }
.cover-side-block h4 {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mute);
  margin: 0 0 12px;
  font-weight: 500;
}
.cover-side-block p {
  font-size: 15px;
  line-height: 1.6;
  color: var(--ink-soft);
  margin: 0 0 10px;
}
.cover-side-block strong { color: var(--ink); font-weight: 600; }

/* ---------- LANDING : TOC table ---------- */
.toc-section {
  max-width: var(--maxw); margin: 0 auto;
  padding: 96px 32px 32px;
}
.toc-section-header {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: baseline;
  gap: 24px;
  margin-bottom: 48px;
}
.toc-title {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
  font-size: clamp(48px, 5vw, 72px);
  line-height: 1;
  margin: 0;
  letter-spacing: -0.02em;
}
.toc-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mute);
}
.part-group { margin-bottom: 56px; }
.part-label {
  display: grid;
  grid-template-columns: 80px 1fr auto;
  align-items: baseline;
  gap: 24px;
  padding-bottom: 14px;
  margin-bottom: 8px;
  border-bottom: 1px solid var(--ink);
}
.part-roman {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 32px;
  color: var(--accent);
  line-height: 1;
}
.part-name {
  font-weight: 600;
  font-size: 16px;
  letter-spacing: -0.01em;
}
.part-count {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--mute);
}

.chapter-row {
  display: grid;
  grid-template-columns: 80px 1fr 60px;
  gap: 24px;
  padding: 22px 0;
  border-bottom: 1px solid var(--rule-soft);
  color: var(--ink);
  position: relative;
  transition: padding-left .25s ease, color .2s;
}
.chapter-row:hover {
  text-decoration: none;
  padding-left: 16px;
  color: var(--accent);
}
.chapter-row::before {
  content: ''; position: absolute; left: 0; top: 50%;
  width: 0; height: 1px; background: var(--accent);
  transition: width .25s ease;
  transform: translateY(-50%);
}
.chapter-row:hover::before { width: 12px; }
.chapter-no {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 38px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--accent);
  font-feature-settings: "tnum";
}
.chapter-cell {
  display: flex; flex-direction: column; gap: 6px;
  min-width: 0;
}
.chapter-row-title {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.3;
}
.chapter-row-thesis {
  font-size: 14.5px;
  color: var(--ink-soft);
  line-height: 1.55;
  max-width: 700px;
}
.chapter-go {
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--mute);
  text-align: right;
  align-self: center;
  transition: color .2s, transform .25s;
}
.chapter-row:hover .chapter-go {
  color: var(--accent); transform: translateX(4px);
}

/* ---------- LANDING : appendices ---------- */
.appendix-rail {
  max-width: var(--maxw); margin: 0 auto;
  padding: 64px 32px 96px;
  border-top: 1px solid var(--rule);
}
.appendix-rail-title {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 40px;
  margin: 32px 0 32px;
  letter-spacing: -0.02em;
}
.appendix-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 0;
  border: 1px solid var(--rule);
}
.appendix-card {
  display: block;
  padding: 32px 28px;
  border-right: 1px solid var(--rule);
  color: var(--ink);
  background: var(--card);
  transition: background .2s;
  position: relative;
}
.appendix-card:last-child { border-right: none; }
.appendix-card:hover {
  text-decoration: none;
  background: var(--accent-tint);
}
:root[data-theme="dark"] .appendix-card:hover { background: var(--accent-tint); color: var(--accent-deep); }
.appendix-card .a-eyebrow {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mute);
  display: block; margin-bottom: 16px;
}
.appendix-card .a-symbol {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 56px;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 12px;
  display: block;
}
.appendix-card .a-title {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 8px;
}
.appendix-card .a-desc {
  font-size: 13.5px;
  color: var(--ink-soft);
  line-height: 1.55;
  margin: 0;
}

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 40px 32px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--mute);
}
.site-footer-inner {
  max-width: var(--maxw); margin: 0 auto;
  display: flex; flex-wrap: wrap; gap: 24px; justify-content: space-between;
}
.site-footer a { color: var(--ink-soft); }
.site-footer a:hover { color: var(--accent); }

/* =================================================================
 * CHAPTER PAGE
 * ================================================================= */

.ch-masthead {
  position: relative;
  max-width: var(--maxw); margin: 0 auto;
  padding: 64px 32px 56px;
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 56px;
  align-items: end;
  border-bottom: 1px solid var(--ink);
}
.ch-masthead-num {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
  font-size: clamp(180px, 22vw, 280px);
  line-height: 0.78;
  letter-spacing: -0.05em;
  color: var(--accent);
  margin: 0;
  font-feature-settings: "tnum";
}
.ch-masthead-right {
  display: flex; flex-direction: column; gap: 22px;
  padding-bottom: 10px;
}
.ch-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mute);
  display: flex; gap: 16px;
}
.ch-eyebrow span::before {
  content: '· '; color: var(--rule); padding-right: 4px;
}
.ch-eyebrow span:first-child::before { display: none; }
.ch-title {
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(36px, 4.6vw, 64px);
  line-height: 1.05;
  letter-spacing: -0.035em;
  margin: 0;
  color: var(--ink);
}
.ch-thesis {
  font-family: var(--font-display);
  font-style: italic;
  font-size: clamp(20px, 2vw, 26px);
  line-height: 1.4;
  letter-spacing: -0.01em;
  color: var(--ink-soft);
  max-width: 720px;
  margin: 0;
  padding: 0;
}

/* layout: marginalia TOC + main body */
.ch-body-shell {
  max-width: var(--maxw); margin: 0 auto;
  padding: 64px 32px 96px;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 80px;
  align-items: start;
}
.ch-toc {
  position: sticky; top: 96px;
  font-size: 13px;
}
.ch-toc-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mute);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}
.ch-toc ol {
  list-style: none; margin: 0; padding: 0;
  counter-reset: tocnum;
}
.ch-toc li {
  counter-increment: tocnum;
  line-height: 1.45;
}
.ch-toc a {
  display: grid;
  grid-template-columns: 22px 1fr;
  gap: 8px;
  padding: 6px 0;
  color: var(--ink-soft);
  font-size: 13px;
  border-left: none;
  letter-spacing: -0.005em;
}
.ch-toc a::before {
  content: counter(tocnum, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--mute);
  letter-spacing: 0;
  padding-top: 3px;
}
.ch-toc a:hover { color: var(--accent); text-decoration: none; }
.ch-toc a.active { color: var(--accent); font-weight: 600; }
.ch-toc a.active::before { color: var(--accent); }

/* main body */
.ch-body {
  max-width: var(--col);
  font-size: 17px;
  line-height: 1.8;
  color: var(--ink);
}
.ch-body p { margin: 0 0 18px; }
/* Lead paragraph: slightly larger, slightly more elegant */
.ch-body > p:first-of-type {
  font-size: 19px;
  line-height: 1.65;
  color: var(--ink);
  margin-bottom: 24px;
  padding-left: 14px;
  border-left: 2px solid var(--rule);
}
/* Style any stray h1 (e.g. in appendices) so it doesn't dominate */
.ch-body h1 {
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: 30px;
  letter-spacing: -0.025em;
  line-height: 1.1;
  margin: 56px 0 18px;
}
.ch-body h2 {
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: 26px;
  letter-spacing: -0.025em;
  line-height: 1.15;
  margin: 64px 0 18px;
  position: relative;
  padding-top: 28px;
  scroll-margin-top: 96px;
}
.ch-body h2::before {
  content: '§';
  font-family: var(--font-display);
  font-style: italic;
  position: absolute;
  top: 16px; left: -28px;
  font-size: 28px;
  color: var(--accent);
  font-weight: 400;
}
.ch-body h2::after {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px; background: var(--rule);
}
.ch-body h2:first-child { margin-top: 0; padding-top: 0; }
.ch-body h2:first-child::after { display: none; }
.ch-body h2:first-child::before { top: -4px; }
.ch-body h3 {
  font-family: var(--font-sans);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 40px 0 12px;
}
.ch-body h4 {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mute);
  margin: 28px 0 10px;
  font-weight: 600;
}
.ch-body strong { color: var(--ink); font-weight: 700; }
.ch-body em { font-style: italic; }
.ch-body ul, .ch-body ol { padding-left: 24px; margin: 0 0 20px; }
.ch-body li { margin-bottom: 6px; }
.ch-body ul li::marker { color: var(--accent); }
.ch-body ol li::marker { color: var(--mute); font-family: var(--font-mono); }

/* pull-quote / blockquote */
.ch-body blockquote {
  margin: 32px 0;
  padding: 4px 0 4px 28px;
  font-family: var(--font-display);
  font-style: italic;
  font-size: 22px;
  line-height: 1.45;
  letter-spacing: -0.01em;
  color: var(--ink);
  border-left: 2px solid var(--accent);
}
.ch-body blockquote p { margin: 0; }

/* "wiki 미확정" inline marker — muted forest, quiet but distinct */
.ch-body strong.alert-tag {
  color: var(--alert);
  background: var(--alert-tint);
  padding: 1px 8px;
  border-radius: 2px;
  font-weight: 600;
  font-size: 0.92em;
  letter-spacing: -0.005em;
  white-space: nowrap;
}

/* hr */
.ch-body hr {
  border: none;
  margin: 44px auto;
  width: 60px;
  height: 16px;
  position: relative;
}
.ch-body hr::before {
  content: '§§';
  position: absolute; left: 0; right: 0; top: 0;
  text-align: center;
  font-family: var(--font-display);
  font-style: italic;
  color: var(--mute);
  font-size: 18px;
  letter-spacing: 0.4em;
}

/* inline code */
.ch-body :not(pre) > code {
  background: transparent;
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.86em;
  padding: 1px 5px;
  border: 1px solid var(--rule);
  border-radius: 3px;
  white-space: nowrap;
  font-weight: 500;
}
:root[data-theme="dark"] .ch-body :not(pre) > code { color: var(--accent-deep); }

/* code blocks */
.ch-body pre {
  background: var(--code-bg);
  color: var(--code-fg);
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  padding: 24px 22px;
  overflow-x: auto;
  margin: 24px 0;
  border-radius: 2px;
  position: relative;
  border: 1px solid var(--ink);
  box-shadow: 6px 6px 0 var(--rule);
}
.ch-body pre code {
  background: none;
  border: none; padding: 0;
  color: inherit; font-size: inherit; font-family: inherit;
  white-space: pre;
}
.ch-body pre::before {
  content: attr(data-lang);
  position: absolute; top: 8px; right: 12px;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.2em;
  color: var(--code-mute);
  text-transform: uppercase;
}

/* tables — hairline */
.ch-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 28px 0;
  font-size: 14px;
  font-family: var(--font-sans);
}
.ch-body thead th {
  text-align: left;
  font-weight: 700;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--ink);
  padding: 12px 14px 10px;
  background: transparent;
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink);
}
.ch-body tbody td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--rule-soft);
  vertical-align: top;
  color: var(--ink-soft);
}
.ch-body tbody tr:hover td { background: var(--card); }
.ch-body table code { white-space: normal; }

/* mermaid block */
.ch-body .mermaid {
  background: var(--card);
  border: 1px solid var(--rule);
  border-radius: 0;
  padding: 28px;
  margin: 28px 0;
  overflow-x: auto;
  text-align: center;
  background-image:
    linear-gradient(to right, var(--rule-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--rule-soft) 1px, transparent 1px);
  background-size: 24px 24px;
  background-position: -1px -1px;
}

/* page nav */
.page-nav {
  max-width: var(--maxw); margin: 0 auto;
  padding: 0 32px 80px;
  border-top: 1px solid var(--ink);
  padding-top: 32px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--rule);
}
.navlink {
  display: block;
  padding: 28px 28px;
  background: var(--paper);
  color: var(--ink);
  transition: background .2s;
}
.navlink:hover { text-decoration: none; background: var(--card); color: var(--accent); }
.navlink .nav-eyebrow {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--mute);
  margin-bottom: 10px;
}
.navlink .nav-no {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 36px;
  line-height: 1;
  color: var(--accent);
  margin-right: 12px;
  vertical-align: middle;
}
.navlink .nav-title {
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.02em;
  display: inline-block;
  vertical-align: middle;
}
.navlink.next { text-align: right; }
.navlink.next .nav-no { margin: 0 0 0 12px; }

/* ---------- Appendix page reuse ch-body styles ---------- */
.appendix-shell {
  max-width: var(--maxw); margin: 0 auto;
  padding: 64px 32px 96px;
  border-bottom: 1px solid var(--ink);
}
.appendix-shell .ch-body { max-width: 880px; }
.appendix-hero {
  display: grid; grid-template-columns: auto 1fr; gap: 40px; align-items: end;
  padding-bottom: 48px;
  margin-bottom: 48px;
  border-bottom: 1px solid var(--ink);
}
.appendix-hero .ch-masthead-num { font-size: 160px; }

/* code highlighting (custom, lightweight) — overrides hljs default */
.hljs { background: transparent !important; padding: 0 !important; color: var(--code-fg) !important; }
.hljs-keyword, .hljs-type, .hljs-built_in { color: var(--code-keyword); }
.hljs-string, .hljs-attr { color: var(--code-string); }
.hljs-number, .hljs-literal { color: var(--code-accent); }
.hljs-comment, .hljs-meta { color: var(--code-comment); font-style: italic; }
.hljs-function .hljs-title, .hljs-title.function_ { color: var(--code-accent); }
.hljs-variable, .hljs-params { color: var(--code-fg); }

/* ---------- entry animation (subtle) ---------- */
@keyframes rise {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
.cover-eyebrow { animation: rise .5s ease both; animation-delay: .04s; }
.cover-title { animation: rise .7s ease both; animation-delay: .1s; }
.cover-korean { animation: rise .6s ease both; animation-delay: .2s; }
.cover-meta { animation: rise .6s ease both; animation-delay: .3s; }
.cover-side { animation: rise .6s ease both; animation-delay: .35s; }

.ch-masthead-num { animation: rise .5s ease both; animation-delay: .05s; }
.ch-masthead-right > * { animation: rise .55s ease both; }
.ch-masthead-right > *:nth-child(1) { animation-delay: .12s; }
.ch-masthead-right > *:nth-child(2) { animation-delay: .18s; }
.ch-masthead-right > *:nth-child(3) { animation-delay: .24s; }

/* prefers-reduced-motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
  html { scroll-behavior: auto; }
}

/* ---------- responsive ---------- */
@media (max-width: 1024px) {
  .cover { grid-template-columns: 1fr; gap: 48px; }
  .cover-side { border-left: none; border-top: 1px solid var(--rule); padding: 32px 0 0 0; }
  .ch-masthead { grid-template-columns: 1fr; gap: 8px; align-items: start; }
  .ch-masthead-num { font-size: clamp(140px, 30vw, 200px); margin-bottom: 8px; }
  .ch-body-shell { grid-template-columns: 1fr; gap: 32px; }
  .ch-toc {
    position: static;
    border: 1px solid var(--rule);
    padding: 18px 20px;
    background: var(--card);
  }
  .appendix-grid { grid-template-columns: 1fr; }
  .appendix-card { border-right: none; border-bottom: 1px solid var(--rule); }
  .appendix-card:last-child { border-bottom: none; }
}

@media (max-width: 720px) {
  .topnav-inner { padding: 12px 18px; grid-template-columns: 1fr auto; }
  .topnav-center { display: none; }
  .cover, .toc-section, .appendix-rail, .ch-masthead, .ch-body-shell, .page-nav, .appendix-shell {
    padding-left: 20px; padding-right: 20px;
  }
  .cover-title { font-size: clamp(44px, 12vw, 72px); }
  .chapter-row {
    grid-template-columns: 56px 1fr;
    gap: 16px; padding: 18px 0;
  }
  .chapter-no { font-size: 30px; }
  .chapter-go { display: none; }
  .part-label { grid-template-columns: 56px 1fr; }
  .part-label .part-count { grid-column: 2; }
  .ch-body h2::before { display: none; }
  .ch-body p:first-of-type::first-letter { font-size: 3em; }
  .ch-body pre { box-shadow: 3px 3px 0 var(--rule); }
  .page-nav { grid-template-columns: 1fr; gap: 1px; }
  .navlink.next { text-align: left; }
  .navlink.next .nav-no { margin: 0 12px 0 0; }
}