:root {
  --ink: #1a1a1a;
  --ink-soft: #3a3a3a;
  --ink-mute: #6a6a6a;
  --paper: #fafaf7;
  --paper-alt: #f2f0e9;
  --line: #d8d4c8;
  --accent: #7a2b1e;
  --accent-soft: #b04a35;
  --gold: #a58c4a;
  --shadow: 0 1px 2px rgba(26,26,26,0.06);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Noto Serif KR", "Times New Roman", serif;
  font-weight: 400;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 32px;
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--line);
  background: var(--paper);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  background: rgba(250,250,247,0.94);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 20px;
  padding-bottom: 20px;
  gap: 32px;
  flex-wrap: wrap;
}
.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.logo { color: var(--accent); flex-shrink: 0; }
.brand-primary {
  font-family: "Inter", sans-serif;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--ink);
}
.brand-secondary {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  color: var(--ink-mute);
  letter-spacing: 0.02em;
}
.topnav {
  display: flex;
  gap: 22px;
  font-family: "Inter", sans-serif;
  font-size: 13px;
  font-weight: 500;
}
.topnav a {
  color: var(--ink-soft);
  text-decoration: none;
  padding: 4px 0;
  border-bottom: 1px solid transparent;
  transition: all 0.2s;
}
.topnav a:hover { color: var(--accent); border-bottom-color: var(--accent); }

/* Hero */
.hero {
  padding: 100px 0 90px;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, var(--paper) 0%, var(--paper-alt) 100%);
}
.eyebrow {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
  margin: 0 0 24px;
}
.hero h1 {
  font-size: clamp(42px, 6vw, 76px);
  line-height: 1.05;
  margin: 0 0 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--ink);
}
.hero-en {
  font-family: "Inter", sans-serif;
  font-weight: 300;
  font-size: 0.55em;
  color: var(--ink-mute);
  letter-spacing: 0.01em;
}
.hero-sub {
  font-size: 18px;
  max-width: 780px;
  color: var(--ink-soft);
  margin: 0 0 48px;
  line-height: 1.7;
}
.hero-sub strong { color: var(--accent); font-weight: 600; }
.hero-meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
  padding: 24px 0;
  border-top: 1px solid var(--line);
  max-width: 780px;
}
.hero-meta > div {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.hero-meta .k {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-mute);
}
.hero-meta .v {
  font-size: 15px;
  color: var(--ink);
}
.hero-meta a { color: var(--accent); text-decoration: none; }
.hero-meta a:hover { text-decoration: underline; }

/* Sections */
.section {
  padding: 90px 0;
  border-bottom: 1px solid var(--line);
}
.section.alt { background: var(--paper-alt); }
.section h2 {
  font-size: 34px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 16px;
  color: var(--ink);
}
.section h3 {
  font-size: 20px;
  font-weight: 600;
  margin: 40px 0 16px;
  color: var(--ink);
  letter-spacing: -0.005em;
}
.section-lead {
  font-size: 17px;
  color: var(--ink-soft);
  max-width: 780px;
  margin: 0 0 48px;
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
}
@media (max-width: 720px) {
  .grid-2 { grid-template-columns: 1fr; gap: 32px; }
}

/* Doc list */
.doc-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 24px;
}
.doc {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 32px;
  padding: 32px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 4px;
  transition: transform 0.2s, box-shadow 0.2s;
}
.section.alt .doc { background: var(--paper); }
.doc:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(26,26,26,0.08);
}
.doc-number {
  font-family: "Inter", sans-serif;
  font-size: 56px;
  font-weight: 200;
  color: var(--gold);
  line-height: 1;
  letter-spacing: -0.02em;
}
.doc h3 {
  margin: 0 0 4px;
  font-size: 22px;
  font-weight: 600;
}
.doc-en {
  font-family: "Inter", sans-serif;
  font-size: 13px;
  color: var(--ink-mute);
  margin: 0 0 14px;
  letter-spacing: 0.01em;
}
.doc-meta {
  display: flex;
  gap: 16px;
  font-family: "Inter", sans-serif;
  font-size: 12px;
  color: var(--ink-mute);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin: 0 0 16px;
}
.doc-meta span::after { content: "·"; margin-left: 16px; color: var(--line); }
.doc-meta span:last-child::after { content: ""; }
.doc p {
  margin: 0 0 20px;
  color: var(--ink-soft);
  font-size: 15.5px;
  line-height: 1.7;
}
.doc-links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.btn {
  display: inline-block;
  padding: 12px 18px;
  margin: 4px 4px 4px 0;
  min-height: 44px;
  line-height: 22px;
  vertical-align: middle;
  background: var(--accent);
  color: var(--paper);
  text-decoration: none;
  font-family: "Inter", sans-serif;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  border-radius: 2px;
  border: 1px solid var(--accent);
  transition: all 0.2s;
}
.btn:hover { background: var(--accent-soft); border-color: var(--accent-soft); }
.btn.ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line);
}
.btn.ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: transparent;
}

@media (max-width: 640px) {
  .doc { grid-template-columns: 1fr; gap: 16px; padding: 24px; }
  .doc-number { font-size: 40px; }
}

/* Chronology table */
.chrono, .precedence, .glossary {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0 40px;
  font-size: 15px;
}
.chrono th, .chrono td,
.precedence th, .precedence td,
.glossary th, .glossary td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.chrono th, .precedence th, .glossary th {
  background: var(--paper-alt);
  font-family: "Inter", sans-serif;
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-mute);
  border-bottom: 2px solid var(--line);
}
.section.alt .chrono th, .section.alt .precedence th, .section.alt .glossary th {
  background: var(--paper);
}
.chrono td:first-child, .precedence td:nth-child(2), .precedence td:nth-child(4) {
  font-family: "Inter", sans-serif;
  font-size: 14px;
  color: var(--ink-mute);
  white-space: nowrap;
}
.precedence td.lead {
  color: var(--accent);
  font-weight: 600;
  font-family: "Inter", sans-serif;
}

/* Ten layers */
.ten-layers {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 12px;
  margin: 24px 0 40px;
}
.layer {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 20px 16px;
  border-radius: 3px;
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.section.alt .layer { background: var(--paper); }
.layer .n {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  color: var(--gold);
  font-weight: 500;
  letter-spacing: 0.1em;
}
.layer .name {
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
}
.layer .desc {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  color: var(--ink-mute);
  letter-spacing: 0.02em;
}

/* Five-layer thesis list */
.five-layer {
  list-style: none;
  padding: 0;
  margin: 24px 0;
  display: grid;
  gap: 12px;
}
.five-layer li {
  padding: 16px 20px;
  background: var(--paper);
  border-left: 3px solid var(--accent);
  border-radius: 2px;
  color: var(--ink-soft);
  font-size: 15.5px;
}
.section.alt .five-layer li { background: var(--paper); }
.five-layer strong { color: var(--ink); font-weight: 600; }

/* Channels */
.channels {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
  margin-top: 32px;
}
.channel {
  background: var(--paper-alt);
  padding: 24px;
  border-radius: 3px;
  border: 1px solid var(--line);
}
.section:not(.alt) .channel { background: var(--paper-alt); }
.channel h4 {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 14px;
  font-weight: 600;
}
.channel ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 6px;
  font-size: 14px;
  color: var(--ink-soft);
}

/* Citation blockquote */
.cite {
  margin: 24px 0;
  padding: 24px 32px;
  border-left: 3px solid var(--gold);
  background: var(--paper);
  font-family: "Inter", sans-serif;
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.7;
}
.section.alt .cite { background: var(--paper); }
.cite em { color: var(--ink); }

/* Footer */
.site-footer {
  background: var(--ink);
  color: var(--paper);
  padding: 60px 0 30px;
  font-family: "Inter", sans-serif;
  font-size: 13px;
}
.foot-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
@media (max-width: 720px) {
  .foot-grid { grid-template-columns: 1fr; gap: 24px; }
}
.foot-title {
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 12px;
}
.foot-sub {
  color: rgba(250,250,247,0.55);
  font-size: 12px;
  margin-top: 4px;
}
.site-footer a { color: var(--paper); text-decoration: none; border-bottom: 1px solid rgba(250,250,247,0.3); }
.site-footer a:hover { border-bottom-color: var(--paper); }
.foot-bottom {
  padding-top: 24px;
  color: rgba(250,250,247,0.4);
  font-size: 11px;
  letter-spacing: 0.03em;
}

/* Language navigation */
.langnav {
  display: flex;
  gap: 4px;
  align-items: center;
  margin-left: 20px;
  padding-left: 20px;
  border-left: 1px solid var(--line);
}
.langnav a {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.05em;
  padding: 4px 8px;
  border-radius: 3px;
  color: var(--ink-mute);
  text-decoration: none;
  transition: all 0.15s ease;
}
.langnav a:hover { color: var(--ink); background: var(--paper-alt); }
.langnav a.active {
  color: var(--paper);
  background: var(--accent);
}
@media (max-width: 900px) {
  .langnav { margin-left: 0; padding-left: 0; border-left: none; margin-top: 8px; }
}

/* Hero English subtitle */
.hero-en {
  display: block;
  font-family: "Inter", sans-serif;
  font-weight: 300;
  font-size: 0.7em;
  color: var(--ink-mute);
  letter-spacing: 0.02em;
  margin-top: 8px;
}

/* Doc English subtitle */
.doc-en {
  font-family: "Inter", sans-serif;
  font-style: normal;
  font-size: 14px;
  color: var(--ink-mute);
  letter-spacing: 0.01em;
  margin: 4px 0 12px 0;
  font-weight: 400;
}

/* Ten layers grid */
.ten-layers {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 12px;
  margin: 24px 0 40px 0;
}
@media (max-width: 720px) {
  .ten-layers { grid-template-columns: repeat(2, 1fr); }
}
.layer {
  border: 1px solid var(--line);
  padding: 16px 14px;
  background: var(--paper);
  border-radius: 4px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  transition: all 0.2s ease;
}
.layer:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}
.layer .n {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 0.1em;
}
.layer .name {
  font-weight: 600;
  font-size: 15px;
  color: var(--ink);
}
.layer .desc {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  color: var(--ink-mute);
  letter-spacing: 0.01em;
}

/* Precedence table */
.precedence {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0 40px 0;
  font-size: 15px;
}
.precedence th {
  text-align: left;
  padding: 12px 14px;
  background: var(--paper-alt);
  border-bottom: 2px solid var(--ink);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  color: var(--ink);
}
.precedence td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.precedence tr:last-child td { border-bottom: none; }
.precedence .lead {
  font-weight: 700;
  color: var(--accent);
  font-family: "Inter", sans-serif;
  letter-spacing: 0.01em;
}

/* Five-layer list */
.five-layer {
  list-style: none;
  padding: 0;
  margin: 16px 0 24px 0;
  display: grid;
  gap: 10px;
}
.five-layer li {
  padding: 14px 18px;
  background: var(--paper);
  border-left: 3px solid var(--accent);
  border-radius: 0 4px 4px 0;
  font-size: 15px;
}
.five-layer li strong {
  display: inline-block;
  min-width: 130px;
  color: var(--accent);
  font-weight: 600;
}

/* Channel cards */
.channels {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin: 24px 0;
}
@media (max-width: 900px) {
  .channels { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 520px) {
  .channels { grid-template-columns: 1fr; }
}
.channel {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 22px 20px;
  border-radius: 4px;
}
.channel h4 {
  margin: 0 0 14px 0;
  font-family: "Inter", sans-serif;
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}
.channel ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.channel li {
  padding: 6px 0;
  font-size: 14px;
  color: var(--ink-soft);
  border-bottom: 1px dashed var(--line);
}
.channel li:last-child { border-bottom: none; }

/* Concept cards */
.concepts {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
  margin: 24px 0;
}
@media (max-width: 900px) {
  .concepts { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 520px) {
  .concepts { grid-template-columns: 1fr; }
}
.concept-card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 22px 18px;
  text-decoration: none;
  color: inherit;
  transition: all 0.2s ease;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.concept-card:hover {
  border-color: var(--accent);
  background: linear-gradient(180deg, var(--paper) 0%, var(--paper-alt) 100%);
  transform: translateY(-3px);
  box-shadow: 0 6px 12px rgba(122,43,30,0.08);
}
.concept-title {
  font-family: "Inter", sans-serif;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.01em;
  color: var(--accent);
}
.concept-ko {
  font-family: "Noto Serif KR", serif;
  font-weight: 600;
  font-size: 17px;
  color: var(--ink);
}
.concept-year {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  color: var(--ink-mute);
  letter-spacing: 0.05em;
  margin-top: auto;
}

/* Citation blocks */
.cite {
  border-left: 4px solid var(--accent);
  padding: 14px 20px;
  margin: 12px 0 24px 0;
  background: var(--paper);
  font-family: "Inter", sans-serif;
  font-size: 14px;
  color: var(--ink-soft);
  border-radius: 0 4px 4px 0;
}
.cite em { font-style: italic; color: var(--ink); }
.bibtex {
  background: #1a1a1a;
  color: #f2f0e9;
  padding: 20px 22px;
  border-radius: 4px;
  font-family: "SF Mono", Consolas, monospace;
  font-size: 13px;
  line-height: 1.6;
  overflow-x: auto;
  margin: 12px 0 24px 0;
}

/* Grid-2 helper */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
@media (max-width: 720px) {
  .grid-2 { grid-template-columns: 1fr; gap: 24px; }
}
.grid-2 h3 {
  font-family: "Inter", sans-serif;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin: 0 0 12px 0;
  font-weight: 600;
}

/* Section-lead */
.section-lead {
  color: var(--ink-mute);
  font-size: 16px;
  margin: -8px 0 24px 0;
  max-width: 720px;
}

/* Concept detail page layout */
.concept-detail {
  padding: 60px 0;
}
.concept-detail .eyebrow {
  font-family: "Inter", sans-serif;
  font-size: 12px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}
.concept-detail h1 {
  font-size: 3.2em;
  line-height: 1.15;
  margin: 12px 0 8px 0;
}
.concept-detail .subtitle-ko {
  font-size: 1.8em;
  font-weight: 400;
  color: var(--ink-soft);
  margin: 0 0 32px 0;
}
.attr-table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 15px;
}
.attr-table th {
  text-align: left;
  width: 180px;
  padding: 10px 16px 10px 0;
  vertical-align: top;
  color: var(--accent);
  font-family: "Inter", sans-serif;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 600;
  border-bottom: 1px solid var(--line);
}
.attr-table td {
  padding: 10px 0;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
}