/* ============================================================
   RESEARCH NOTES — per-chapter research documentation pages
   Editorial layout with axis-character watermark (data-book attr)
   Inherits tokens from styles.css / fulltext.css
   ============================================================ */

.rn-page {
  background: var(--bg-deep);
  color: var(--text-primary);
  font-family: var(--serif-kr);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

.rn-main {
  max-width: 820px;
  margin: 0 auto;
  padding: 96px 24px 120px;
}

/* ============================================================
   HEADER — hero with axis-char watermark + roman numeral
   ============================================================ */
.rn-header {
  position: relative;
  padding: 24px 0 44px;
  margin-bottom: 56px;
  border-bottom: 1px solid var(--border);
  overflow: hidden;
  isolation: isolate;
  text-align: center;
}

.rn-header::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--serif-kr);
  font-size: 340px;
  font-weight: 700;
  line-height: 1;
  color: rgba(212, 178, 85, 0.035);
  pointer-events: none;
  z-index: 0;
  white-space: nowrap;
  user-select: none;
}

.rn-header > * {
  position: relative;
  z-index: 1;
}

.rn-page[data-book="1"] .rn-header::before { content: '時'; }
.rn-page[data-book="2"] .rn-header::before { content: '空'; }
.rn-page[data-book="3"] .rn-header::before { content: '資'; }
.rn-page[data-book="4"] .rn-header::before { content: '制'; }
.rn-page[data-book="5"] .rn-header::before { content: '國'; }
.rn-page[data-book="6"] .rn-header::before { content: '個'; }

.rn-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  font-family: var(--sans-en);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--accent-gold);
  margin-bottom: 22px;
}

.rn-eyebrow::before,
.rn-eyebrow::after {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--accent-gold-dim);
}

/* Roman numeral accent, injected by data-book */
.rn-page .rn-header .rn-page-title::before {
  display: block;
  font-family: var(--serif-en);
  font-style: italic;
  font-weight: 400;
  font-size: 48px;
  line-height: 1;
  letter-spacing: 2px;
  color: var(--accent-gold);
  opacity: 0.9;
  margin-bottom: 16px;
}

.rn-page[data-book="1"] .rn-header .rn-page-title::before { content: 'I'; }
.rn-page[data-book="2"] .rn-header .rn-page-title::before { content: 'II'; }
.rn-page[data-book="3"] .rn-header .rn-page-title::before { content: 'III'; }
.rn-page[data-book="4"] .rn-header .rn-page-title::before { content: 'IV'; }
.rn-page[data-book="5"] .rn-header .rn-page-title::before { content: 'V'; }
.rn-page[data-book="6"] .rn-header .rn-page-title::before { content: 'VI'; }

.rn-chapter-label {
  font-family: var(--serif-kr);
  font-size: 15px;
  font-style: italic;
  color: var(--text-muted);
  margin-bottom: 20px;
  letter-spacing: 0.2px;
}

.rn-page-title {
  font-family: var(--serif-kr);
  font-size: clamp(30px, 4.4vw, 44px);
  font-weight: 700;
  line-height: 1.22;
  color: var(--text-primary);
  margin: 0 0 24px;
  letter-spacing: -0.01em;
}

.rn-intro {
  max-width: 620px;
  margin: 0 auto;
  font-family: var(--serif-kr);
  font-size: 15px;
  line-height: 1.9;
  color: var(--text-secondary);
}

/* ============================================================
   SUMMARY BLOCK — TOC of research docs
   ============================================================ */
.rn-summary {
  position: relative;
  padding: 26px 30px 24px;
  margin-bottom: 64px;
  background: linear-gradient(180deg, rgba(22, 22, 34, 0.6), var(--bg-card));
  border: 1px solid var(--border);
  border-left: 2px solid var(--accent-gold-dim);
  border-radius: 3px;
}

.rn-summary-label {
  font-family: var(--sans-en);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 2.5px;
  text-transform: uppercase;
  color: var(--accent-gold);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.rn-summary-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--accent-gold-dim), transparent 80%);
}

.rn-summary-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.rn-summary-list li {
  font-family: var(--sans-kr);
  font-size: 14px;
  color: var(--text-secondary);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px dotted rgba(255, 255, 255, 0.05);
  transition: padding 0.25s ease;
}

.rn-summary-list li:last-child {
  border-bottom: none;
}

.rn-summary-list li:hover {
  padding-left: 6px;
}

.rn-sum-id {
  font-family: var(--serif-en);
  font-style: italic;
  font-weight: 400;
  color: var(--accent-gold);
  font-size: 13px;
  letter-spacing: 1px;
  padding: 3px 10px;
  border: 1px solid var(--accent-gold-dim);
  border-radius: 2px;
  background: rgba(212, 178, 85, 0.05);
  flex-shrink: 0;
}

.rn-sum-title {
  font-family: var(--serif-kr);
  color: var(--text-primary);
  flex: 1;
  min-width: 200px;
  font-size: 14.5px;
  line-height: 1.55;
}

.rn-sum-count {
  font-family: var(--sans-en);
  font-size: 11px;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.3px;
}

.rn-sum-jump {
  font-family: var(--sans-en);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--accent-gold);
  text-decoration: none;
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 2px;
  background: rgba(212, 178, 85, 0.03);
  transition: all 0.2s ease;
}

.rn-sum-jump:hover {
  color: var(--bg-deep);
  background: var(--accent-gold);
  border-color: var(--accent-gold);
}

/* ============================================================
   RESEARCH DOC SECTIONS
   ============================================================ */
.rn-docs {
  display: flex;
  flex-direction: column;
  gap: 72px;
}

.rn-doc {
  scroll-margin-top: 80px;
}

.rn-doc-header {
  position: relative;
  padding: 0 0 22px;
  margin-bottom: 36px;
  border-bottom: 1px solid var(--border);
}

.rn-doc-header::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 72px;
  height: 2px;
  background: var(--accent-gold);
}

.rn-doc-id {
  display: inline-block;
  font-family: var(--serif-en);
  font-style: italic;
  font-size: 13px;
  font-weight: 400;
  letter-spacing: 1.5px;
  color: var(--accent-gold);
  text-transform: uppercase;
  padding: 3px 10px;
  border: 1px solid var(--accent-gold-dim);
  border-radius: 2px;
  background: rgba(212, 178, 85, 0.04);
  margin-bottom: 14px;
}

.rn-doc-title {
  font-family: var(--serif-kr);
  font-size: clamp(22px, 2.6vw, 28px);
  font-weight: 700;
  color: var(--text-primary);
  margin: 0 0 10px;
  line-height: 1.3;
  letter-spacing: -0.005em;
}

.rn-doc-meta {
  font-family: var(--sans-en);
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.8px;
  font-variant-numeric: tabular-nums;
  text-transform: uppercase;
}

.rn-doc-empty {
  font-family: var(--serif-kr);
  font-size: 14px;
  color: var(--text-muted);
  font-style: italic;
  padding: 16px 0;
}

/* ============================================================
   FACT LIST — numbered editorial entries
   ============================================================ */
.rn-fact-list {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: rn-fact;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.rn-fact {
  position: relative;
  counter-increment: rn-fact;
  padding: 4px 0 4px 44px;
  transition: padding 0.25s ease;
}

.rn-fact::before {
  content: counter(rn-fact, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 4px;
  font-family: var(--serif-en);
  font-style: italic;
  font-size: 13px;
  font-weight: 400;
  color: var(--accent-gold);
  opacity: 0.65;
  letter-spacing: 1px;
  line-height: 1.6;
  width: 30px;
  text-align: right;
  padding-right: 10px;
  border-right: 1px solid var(--accent-gold-dim);
  transition: opacity 0.25s ease, color 0.25s ease;
}

.rn-fact:hover::before {
  opacity: 1;
  color: var(--accent-gold);
}

.rn-fact-text {
  font-family: var(--serif-kr);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.rn-fact-text em {
  font-style: italic;
  color: var(--text-secondary);
}

.rn-fact-text strong {
  font-weight: 700;
  color: var(--accent-gold);
  letter-spacing: 0.01em;
}

.rn-fact-text a {
  color: var(--accent-gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(212, 178, 85, 0.4);
  transition: border-color 0.2s, color 0.2s;
}

.rn-fact-text a:hover {
  color: var(--text-primary);
  border-bottom-color: var(--accent-gold);
}

/* ============================================================
   SOURCE LIST under each fact
   ============================================================ */
.rn-sources {
  list-style: none;
  margin: 0;
  padding: 10px 0 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-top: 1px dotted rgba(212, 178, 85, 0.12);
}

.rn-sources li {
  font-family: var(--sans-kr);
  font-size: 12.5px;
  color: var(--text-muted);
  line-height: 1.65;
  padding-left: 18px;
  position: relative;
}

.rn-sources li::before {
  content: '↳';
  position: absolute;
  left: 0;
  top: 0;
  color: var(--accent-gold);
  opacity: 0.7;
  font-family: var(--sans-en);
  font-size: 12px;
}

.rn-sources li strong {
  font-family: var(--serif-kr);
  color: var(--text-secondary);
  font-weight: 500;
  font-style: italic;
}

.rn-sources li a {
  color: var(--text-secondary);
  text-decoration: none;
  border-bottom: 1px dotted var(--border);
  word-break: break-all;
  transition: color 0.2s, border-color 0.2s;
}

.rn-sources li a:hover {
  color: var(--accent-gold);
  border-bottom-color: var(--accent-gold);
}

.rn-sources li em {
  color: var(--text-secondary);
  font-style: italic;
}

/* ============================================================
   COLLAPSIBLE ALL-SOURCES block
   ============================================================ */
.rn-all-sources {
  margin-top: 44px;
  padding: 22px 26px;
  background: rgba(255, 255, 255, 0.015);
  border: 1px solid var(--border);
  border-left: 2px solid var(--accent-gold-dim);
  border-radius: 3px;
}

.rn-all-sources summary {
  font-family: var(--sans-en);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 2.5px;
  text-transform: uppercase;
  color: var(--accent-gold);
  cursor: pointer;
  list-style: none;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 12px;
}

.rn-all-sources summary::-webkit-details-marker { display: none; }

.rn-all-sources summary::before {
  content: '▸';
  display: inline-block;
  font-size: 10px;
  transition: transform 0.25s ease;
}

.rn-all-sources[open] summary::before {
  transform: rotate(90deg);
}

.rn-all-sources summary::after {
  content: '';
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--accent-gold-dim), transparent 80%);
}

.rn-all-sources[open] summary {
  margin-bottom: 18px;
}

.rn-all-sources ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
  counter-reset: rn-src;
}

.rn-all-sources ul li {
  font-family: var(--sans-kr);
  font-size: 12.5px;
  color: var(--text-muted);
  line-height: 1.65;
  padding: 8px 0 8px 12px;
  border-left: 1px solid rgba(212, 178, 85, 0.08);
  transition: border-color 0.2s ease, padding 0.2s ease;
}

.rn-all-sources ul li:hover {
  border-left-color: var(--accent-gold);
  padding-left: 16px;
}

.rn-all-sources ul li strong {
  display: inline-block;
  font-family: var(--serif-en);
  font-style: italic;
  font-size: 11px;
  font-weight: 400;
  color: var(--accent-gold);
  margin-right: 8px;
  letter-spacing: 0.5px;
}

.rn-all-sources ul li a {
  color: var(--text-secondary);
  text-decoration: none;
  border-bottom: 1px dotted var(--border);
  word-break: break-all;
  transition: color 0.2s, border-color 0.2s;
}

.rn-all-sources ul li a:hover {
  color: var(--accent-gold);
  border-bottom-color: var(--accent-gold);
}

/* ============================================================
   FOOTER NAV
   ============================================================ */
.rn-footer {
  margin-top: 96px;
  padding-top: 36px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  position: relative;
}

.rn-footer::before {
  content: '◆';
  position: absolute;
  top: -8px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 10px;
  color: var(--accent-gold-dim);
  background: var(--bg-deep);
  padding: 0 12px;
}

.rn-footer-link {
  font-family: var(--sans-kr);
  font-size: 13px;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 12px 22px;
  border: 1px solid var(--border);
  border-radius: 3px;
  transition: all 0.25s ease;
  letter-spacing: 0.3px;
  background: rgba(255, 255, 255, 0.015);
}

.rn-footer-link:hover {
  color: var(--accent-gold);
  border-color: var(--accent-gold-dim);
  background: rgba(212, 178, 85, 0.05);
  transform: translateY(-1px);
}

/* ============================================================
   MOBILE
   ============================================================ */
@media (max-width: 720px) {
  .rn-main {
    padding: 72px 18px 96px;
  }
  .rn-header::before {
    font-size: 220px;
  }
  .rn-page .rn-header .rn-page-title::before {
    font-size: 36px;
  }
  .rn-page-title {
    font-size: 28px;
  }
  .rn-doc-title {
    font-size: 21px;
  }
  .rn-summary {
    padding: 20px 22px;
  }
  .rn-summary-list li {
    gap: 8px;
    padding: 8px 0;
  }
  .rn-fact {
    padding-left: 36px;
  }
  .rn-fact::before {
    width: 24px;
    font-size: 11px;
  }
  .rn-fact-text {
    font-size: 14.5px;
  }
  .rn-docs {
    gap: 56px;
  }
  .rn-footer {
    flex-direction: column;
  }
  .rn-footer-link {
    text-align: center;
  }
  .rn-all-sources {
    padding: 18px 20px;
  }
}

@media (max-width: 480px) {
  .rn-header::before {
    font-size: 180px;
  }
  .rn-eyebrow {
    font-size: 10px;
    letter-spacing: 2px;
  }
  .rn-eyebrow::before,
  .rn-eyebrow::after {
    width: 16px;
  }
}