/* Research single paper page — from assets/html/nffd.html */

.research-single {
  --ink: #14171f;
  --ink-2: #2b3240;
  --muted: #6b7280;
  --line: #e4e1da;
  --line-2: #efede6;
  --paper: #fbf9f4;
  --paper-2: #f5f1e8;
  --navy: #0a2540;
  --navy-2: #1a3454;
  --blue: #0052cc;
  --blue-2: #003d99;
  --blue-soft: #e8eef7;
  --sage: #687a6b;
  --gold: #b89d5a;
  --gold-soft: #efe5c7;
  --green-paper: #556b45;
  --red-blood: #8b2635;
  --shadow-sm: 0 2px 8px rgba(10, 37, 64, 0.06);
  --shadow-md: 0 8px 24px rgba(10, 37, 64, 0.08);
  --shadow-lg: 0 16px 48px rgba(10, 37, 64, 0.12);
  --font-base: 'Pretendard', -apple-system, BlinkMacSystemFont, sans-serif;
  --min-font-size: 13px;

  font-family: var(--font-base);
  font-size: var(--min-font-size);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  word-break: keep-all;
}

.research-single,
.research-single *,
.research-single *::before,
.research-single *::after {
  box-sizing: border-box;
}

.research-single a {
  color: inherit;
  text-decoration: none;
}

.research-single em,
.research-single i,
.research-single cite {
  font-style: normal;
}

.research-single.paper-texture {
  position: relative;
}

.research-single.paper-texture::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(59, 45, 26, 0.018) 1px, transparent 1px);
  background-size: 4px 4px;
  pointer-events: none;
  z-index: 0;
}

.research-single.paper-texture > * {
  position: relative;
  z-index: 1;
}

.research-single .container {
  max-width: 1180px;
  margin: 0 auto;
}

@media (max-width: 768px) {
  .research-single .article-meta .container {
    align-items: flex-start;
  }

  .research-single .breadcrumb {
    line-height: 1.5;
  }
}

.research-single .article-meta {
  border-bottom: 1px solid var(--line);
  padding: 14px 0;
  background: rgba(251, 249, 244, 0.6);
}

.research-single .article-meta .container {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 0.04em;
}

.research-single .breadcrumb a {
  color: var(--muted);
}

.research-single .breadcrumb a:hover {
  color: var(--navy);
}

.research-single .article-meta-sep {
  margin: 0 8px;
  color: var(--line);
}

.research-single .article-meta-current {
  color: var(--ink-2);
  font-weight: 600;
}

.research-single .paper-hero {
  padding: 80px 0 64px;
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}

.research-single .hero-eyebrow {
  font-family: var(--font-base);
  font-size: 17px;
  color: var(--sage);
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.research-single .hero-eyebrow .journal {
  color: var(--navy);
  font-weight: 500;
}

.research-single .hero-eyebrow .special-issue {
  color: var(--gold);
  font-weight: 600;
  margin-left: 8px;
}

.research-single .paper-title-en {
  font-family: var(--font-base);
  font-size: 38px;
  font-weight: 600;
  color: var(--navy);
  line-height: 1.25;
  letter-spacing: -0.025em;
  margin-bottom: 14px;
  max-width: 960px;
}

.research-single .paper-title-en em {
  color: var(--sage);
}

.research-single .paper-title-ko {
  font-family: var(--font-base);
  font-size: 22px;
  font-weight: 600;
  color: var(--ink-2);
  margin-bottom: 36px;
  letter-spacing: -0.015em;
}

.research-single .citation-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 28px;
}

.research-single .citation-item {
  padding: 20px 22px;
  border-right: 1px solid var(--line);
}

.research-single .citation-item:last-child {
  border-right: none;
}

.research-single .citation-label {
  font-family: var(--font-base);
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 8px;
  font-weight: 600;
}

.research-single .citation-value {
  font-family: var(--font-base);
  font-size: 15px;
  color: var(--ink);
  font-weight: 500;
  line-height: 1.45;
}

.research-single .citation-value a {
  color: var(--blue);
  font-family: var(--font-base);
  font-size: 13px;
}

.research-single .citation-value a:hover {
  text-decoration: underline;
}

.research-single .citation-value .small-name {
  display: block;
  font-size: 13px;
  color: var(--muted);
  margin-top: 4px;
  font-family: var(--font-base);
  font-weight: 400;
  line-height: 1.4;
}

@media (max-width: 900px) {
  .research-single .citation-grid {
    grid-template-columns: 1fr 1fr;
  }

  .research-single .citation-item {
    border-bottom: 1px solid var(--line);
  }
}

@media (max-width: 540px) {
  .research-single .citation-grid {
    grid-template-columns: 1fr;
  }

  .research-single .citation-item {
    border-right: none;
  }
}

.research-single .paper-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.research-single .paper-action {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 11px 18px;
  background: var(--navy);
  color: #fff !important;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  transition: all 0.2s;
}

.research-single .paper-action:hover {
  background: var(--sage-2);
  transform: translateY(-1px);
}

.research-single .paper-action.alt {
  background: #fff;
  color: var(--navy) !important;
  border: 1px solid var(--line);
}

.research-single .paper-action.alt:hover {
  border-color: var(--sage);
  color: var(--sage) !important;
  background: var(--sage-soft);
}

.research-single .section {
  padding: 80px 0;
  border-bottom: 1px solid var(--line);
}

.research-single .section.alt {
  background: var(--paper-2);
}

.research-single .section-marker {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 32px;
  margin-bottom: 44px;
  align-items: start;
}

.research-single .section-num {
  font-family: var(--font-base);
  font-size: 56px;
  font-weight: 300;
  color: var(--gold);
  line-height: 1;
}

.research-single .section-eyebrow {
  font-family: var(--font-base);
  font-size: 13px;
  font-weight: 600;
  color: var(--sage);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  margin-bottom: 10px;
}

.research-single .section-title {
  font-family: var(--font-base);
  font-size: 34px;
  font-weight: 600;
  color: var(--navy);
  letter-spacing: -0.025em;
  line-height: 1.25;
  margin-bottom: 14px;
}

.research-single .section-title em {
  color: var(--sage);
}

.research-single .section-lede {
  font-family: var(--font-base);
  font-size: 18px;
  line-height: 1.65;
  color: var(--ink-2);
  max-width: 760px;
}

@media (max-width: 768px) {
  .research-single .section-marker {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .research-single .section-num {
    font-size: 40px;
  }

  .research-single .section-title {
    font-size: 26px;
  }

  .research-single .paper-title-en {
    font-size: 26px;
  }
}

.research-single .summary-block {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 64px;
  align-items: start;
}

.research-single .summary-pullquote {
  font-weight: 500;
  font-family: var(--font-base);
  font-size: 24px;
  line-height: 1.5;
  color: var(--navy);
  letter-spacing: -0.025em;
  border-left: 3px solid var(--gold);
  padding-left: 24px;
}

.research-single .summary-pullquote em {
  color: #444;
}

.research-single .summary-text {
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-2);
}

.research-single .summary-text p {
  margin-bottom: 18px;
}

.research-single .summary-text strong {
  color: var(--navy);
  font-weight: 700;
}

@media (max-width: 900px) {
  .research-single .summary-block {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .research-single .summary-pullquote {
    font-size: 24px;
  }
}

.research-single .technique-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  margin: 36px 0 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
}

.research-single .tech-step {
  padding: 32px 28px;
  border-right: 1px solid var(--line);
  position: relative;
}

.research-single .tech-step:last-child {
  border-right: none;
}

.research-single .tech-step .tech-num {
  font-family: var(--font-base);
  font-size: 16px;
  color: var(--gold);
  font-weight: 600;
  margin-bottom: 12px;
}

.research-single .tech-step .tech-name {
  font-family: var(--font-base);
  font-weight: 700;
  font-size: 24px;
  color: var(--navy);
  margin-bottom: 6px;
  letter-spacing: -0.02em;
}

.research-single .tech-step .tech-name-ko {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 14px;
}

.research-single .tech-step .tech-desc {
  font-size: 14px;
  color: var(--ink-2);
  line-height: 1.65;
}

@media (max-width: 768px) {
  .research-single .technique-steps {
    grid-template-columns: 1fr;
  }

  .research-single .tech-step {
    border-right: none;
    border-bottom: 1px solid var(--line);
  }
}

.research-single .differentiator {
  background: var(--paper);
  border-left: 3px solid var(--gold);
  padding: 24px 28px;
  margin-top: 32px;
  border-radius: 4px;
}

.research-single .differentiator-label {
  font-family: var(--font-base);
  font-size: 14px;
  color: var(--gold);
  margin-bottom: 8px;
}

.research-single .differentiator p {
  font-size: 15.5px;
  color: var(--ink-2);
  line-height: 1.7;
}

.research-single .differentiator strong {
  color: var(--navy);
  font-weight: 700;
}

.research-single .press-coverage-intro {
  background: var(--sage-soft);
  border-left: 3px solid var(--sage);
  padding: 24px 28px;
  border-radius: 4px;
  margin-bottom: 36px;
}

.research-single .press-coverage-intro p {
  font-family: var(--font-base);
  font-size: 16px;
  line-height: 1.65;
  color: var(--ink-2);
}

.research-single .press-coverage-intro strong {
  color: var(--navy);
  font-weight: 700;
}

.research-single .press-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.research-single .press-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 26px 28px;
  transition: all 0.25s cubic-bezier(0.2, 0.8, 0.2, 1);
  display: flex;
  flex-direction: column;
}

.research-single .press-card:hover {
  transform: translateY(-3px);
  border-color: var(--sage);
  box-shadow: var(--shadow-md);
}

.research-single .press-card-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px dashed var(--line);
}

.research-single .press-media {
  font-family: var(--font-base);
  font-weight: 600;
  font-size: 18px;
  color: var(--navy);
  letter-spacing: -0.015em;
}

.research-single .press-date {
  font-family: var(--font-base);
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 0.05em;
}

.research-single .press-title {
  font-family: var(--font-base);
  font-size: 16.5px;
  line-height: 1.55;
  color: var(--ink);
  font-weight: 500;
  letter-spacing: -0.015em;
  margin-bottom: 16px;
  flex: 1;
}

.research-single .press-actions {
  display: flex;
  gap: 10px;
  align-items: center;
}

.research-single .press-link {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 13px;
  color: var(--sage);
  font-weight: 600;
}

.research-single .press-card:hover .press-link {
  gap: 8px;
}

.research-single .press-flag {
  font-family: var(--font-base);
  font-size: 13px;
  color: var(--green-paper);
  background: rgba(85, 107, 69, 0.1);
  padding: 3px 8px;
  border-radius: 3px;
  letter-spacing: 0.12em;
  font-weight: 600;
  margin-left: auto;
}

@media (max-width: 768px) {
  .research-single .press-grid {
    grid-template-columns: 1fr;
  }
}

.research-single .citation-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--line);
}

.research-single .citation-tab {
  font-family: var(--font-base);
  font-size: 13px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 14px 22px;
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  font-weight: 600;
  transition: all 0.2s;
}

.research-single .citation-tab.active {
  color: var(--navy);
  border-bottom-color: var(--gold);
}

.research-single .citation-panel {
  background: #fff;
  border: 1px solid var(--line);
  border-top: none;
  padding: 28px 32px;
  display: none;
  border-radius: 0 0 8px 8px;
}

.research-single .citation-panel.active {
  display: block;
}

.research-single .citation-panel pre {
  font-family: var(--font-base);
  font-size: 13px;
  line-height: 1.75;
  color: var(--ink-2);
  white-space: pre-wrap;
  word-break: break-word;
  margin: 0;
}

.research-single .citation-panel .copy-btn {
  margin-top: 18px;
  padding: 8px 14px;
  background: var(--paper-2);
  border: 1px solid var(--line);
  color: var(--ink-2);
  font-size: 13px;
  font-family: var(--font-base);
  cursor: pointer;
  border-radius: 4px;
  font-weight: 600;
  letter-spacing: 0.05em;
}

.research-single .citation-panel .copy-btn:hover {
  background: #fff;
  border-color: var(--navy);
  color: var(--navy);
}

.research-single .schema-callout {
  margin-top: 48px;
  background: #0f172a;
  color: #e2e8f0;
  border-radius: 10px;
  padding: 28px 32px;
}

.research-single .schema-callout-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.research-single .schema-callout-head .badge {
  background: #6fa8ff;
  color: #0a2540;
  padding: 4px 9px;
  border-radius: 3px;
  font-family: var(--font-base);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.research-single .schema-callout-head h4 {
  font-family: var(--font-base);
  font-size: 18px;
  color: #fff;
  font-weight: 500;
  margin: 0;
}

.research-single .schema-callout p {
  font-size: 13.5px;
  color: #94a3b8;
  line-height: 1.65;
  margin-bottom: 14px;
}

.research-single .schema-callout code {
  font-family: var(--font-base);
  font-size: 13px;
  color: #6fa8ff;
  background: rgba(111, 168, 255, 0.08);
  padding: 2px 6px;
  border-radius: 3px;
}

.research-single .related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.research-single .related-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 28px 26px;
  transition: all 0.25s;
  display: flex;
  flex-direction: column;
}

.research-single .related-card:hover {
  transform: translateY(-4px);
  border-color: var(--gold);
  box-shadow: var(--shadow-md);
}

.research-single .related-card .related-flag {
  font-family: var(--font-base);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--muted);
  margin-bottom: 14px;
  font-weight: 600;
}

.research-single .related-card .related-flag.review {
  color: var(--gold);
}

.research-single .related-card .related-flag.pub {
  color: var(--green-paper);
}

.research-single .related-card h4 {
  font-family: var(--font-base);
  font-size: 28px;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 8px;
  letter-spacing: -0.02em;
  line-height: 1.3;
}

.research-single .related-card p {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.6;
  flex: 1;
  margin-bottom: 18px;
}

.research-single .related-card .arrow {
  font-family: var(--font-base);
  color: var(--sage);
  font-size: 14px;
  font-weight: 500;
}

@media (max-width: 768px) {
  .research-single .related-grid {
    grid-template-columns: 1fr;
  }
}

.research-single .cta-section {
  background: var(--navy);
  color: var(--paper);
  padding: 96px 0;
  text-align: center;
}

.research-single .cta-eyebrow {
  font-size: 11px;
  color: var(--gold);
  letter-spacing: 0.24em;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.research-single .cta-title {
  font-size: clamp(28px, 4vw, 48px);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: #fff;
  margin: 0 auto 20px;
}

.research-single .cta-title em {
  color: var(--gold);
}

.research-single .cta-sub {
  font-size: 18px;
  color: rgba(251, 249, 244, 0.75);
  margin: 0 auto 36px;
  line-height: 1.65;
}

.research-single .cta-buttons {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

.research-single .cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 28px;
  font-size: 18px;
  font-weight: 700;
  border-radius: 4px;
  transition: all 0.2s;
}

.research-single .cta-btn.primary {
  background: var(--gold);
  color: var(--navy) !important;
}

.research-single .cta-btn.primary:hover {
  background: #c9af70;
}

.research-single .cta-btn.ghost {
  background: transparent;
  color: #fff !important;
  border: 1px solid rgba(251, 249, 244, 0.3);
}

.research-single .cta-btn.ghost:hover {
  border-color: var(--gold);
  color: var(--gold) !important;
}

@media (max-width: 768px) {
  .research-single .cta-section {
    padding: 64px 0;
  }
}

.research-single .section-eyebrow::before,
.research-single .section-eyebrow::after {
  content: none;
  margin: 0;
}