/* =============================================================
   연구 노트 (Research) — CSS
   ============================================================= */

.research {
  flex: 1;
  background: var(--paper);
}
.research__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--s7) var(--s5) var(--s9);
}

/* ============================================================
   Hero
   ============================================================ */
.research__hero {
  background: var(--paper-deep);
  border-bottom: 1px solid var(--rule-soft);
}
.research__hero-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--s8) var(--s5);
}
.research__hero-eyebrow {
  font-family: var(--font-en);
  font-size: 10.5px;
  letter-spacing: 0.4em;
  text-transform: uppercase;
  color: var(--ink-mute);
  border-top: 2px solid var(--signal);
  padding-top: var(--s4);
  width: max-content;
  max-width: 100%;
  margin-bottom: var(--s5);
}
.research__hero-title {
  font-family: var(--font-kr);
  font-weight: 200;
  font-size: clamp(36px, 5vw, 56px);
  letter-spacing: -0.015em;
  color: var(--ink);
  margin: 0 0 var(--s4);
  line-height: 1.1;
}
.research__hero-sub {
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--ink-soft);
  max-width: 58ch;
  margin: 0;
}
.research__hero-meta {
  display: flex;
  gap: var(--s7);
  margin-top: var(--s6);
  padding-top: var(--s4);
  border-top: 1px solid var(--rule-soft);
}
.research__hero-meta-key {
  font-family: var(--font-en);
  font-size: 10px;
  letter-spacing: 0.4em;
  text-transform: uppercase;
  color: var(--ink-mute);
  margin-bottom: 4px;
}
.research__hero-meta-val {
  font-family: var(--font-cn);
  font-weight: 400;
  font-size: 22px;
  letter-spacing: 0.08em;
  color: var(--ink);
}

/* ============================================================
   섹션
   ============================================================ */
.research__section { margin-bottom: var(--s9); }
.research__section-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  padding-bottom: var(--s4);
  border-bottom: 1px solid var(--rule-soft);
  margin-bottom: var(--s5);
  gap: var(--s5);
}
.research__section-eyebrow {
  font-family: var(--font-cn);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--ink-mute);
  margin-bottom: 4px;
}
.research__section-title {
  font-family: var(--font-kr);
  font-weight: 400;
  font-size: 26px;
  letter-spacing: -0.005em;
  color: var(--ink);
  margin: 0;
}

/* ============================================================
   프로젝트 에세이
   ============================================================ */
.research__focus {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.65fr);
  gap: var(--s6);
  align-items: stretch;
  margin-bottom: var(--s9);
  padding: var(--s6);
  background: var(--paper-deep);
  border: 1px solid var(--rule);
  border-radius: 12px;
}
.research__focus-copy {
  display: flex;
  flex-direction: column;
  gap: var(--s4);
}
.research__focus-eyebrow {
  font-family: var(--font-en);
  font-size: 10.5px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--ink-mute);
}
.research__focus h2 {
  font-family: var(--font-kr);
  font-size: 28px;
  font-weight: 400;
  letter-spacing: -0.01em;
  line-height: 1.25;
  color: var(--ink);
  margin: 0;
}
.research__focus p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
  margin: 0;
  max-width: 78ch;
}
.research__focus-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s3);
  margin-top: var(--s2);
}
.research__focus-actions button {
  min-height: 40px;
  padding: 10px 16px;
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink);
  border-radius: 8px;
  font-family: var(--font-kr);
  font-size: 13px;
  cursor: pointer;
}
.research__focus-actions button.is-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--rule);
}
.research__focus-points {
  display: grid;
  gap: var(--s3);
}
.research__focus-points div {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: var(--s4);
  background: var(--chrome);
  border: 1px solid var(--rule-soft);
  border-radius: 8px;
}
.research__focus-points b {
  font-size: 13px;
  color: var(--ink);
}
.research__focus-points span {
  font-size: 13px;
  line-height: 1.65;
  color: var(--ink-soft);
}

/* 탭 */
.research__tabs {
  display: flex;
  gap: var(--s4);
}
.research__tab {
  font-family: var(--font-kr);
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--ink-mute);
  padding: 6px 0;
  border-bottom: 1px solid transparent;
  cursor: pointer;
  transition: color 120ms ease, border-color 120ms ease;
}
.research__tab:hover { color: var(--ink); }
.research__tab.is-active {
  color: var(--ink);
  border-bottom-color: var(--signal);
  border-bottom-width: 2px;
  padding-bottom: 5px;
}

/* ============================================================
   시리즈 카드
   ============================================================ */
.research__series {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
  border-top: 1px solid var(--rule-soft);
}
.research__series-card {
  padding: var(--s5);
  border-right: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
  display: flex;
  flex-direction: column;
  gap: var(--s3);
  background: var(--paper);
  transition: background 120ms ease;
}
.research__series-card:nth-child(2n) { border-right: 0; }
.research__series-card:hover { background: var(--paper-deep); }
.research__series-card.is-accent {
  background: var(--paper-deep);
  border-left: 3px solid var(--signal);
  padding-left: calc(var(--s5) - 3px);
}
.research__series-card.is-planned { opacity: 0.55; }

.research__series-eyebrow {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  font-family: var(--font-cn);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--ink-mute);
}
.research__series-status {
  font-family: var(--font-en);
  font-size: 10px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  padding: 2px 8px;
  border: 0.5px solid var(--rule);
  border-radius: 2px;
}
.research__series-status--active   { color: var(--signal); border-color: var(--signal); }
.research__series-status--planned  { color: var(--ink-mute); }
.research__series-status--rolling  { color: var(--ink); }

.research__series-title {
  font-family: var(--font-kr);
  font-weight: 500;
  font-size: 24px;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: var(--s2) 0 0;
  line-height: 1.25;
}
.research__series-sub {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.5;
  letter-spacing: 0.005em;
}
.research__series-desc {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
  margin: var(--s2) 0 var(--s3);
}

.research__series-meta {
  margin-top: auto;
  padding-top: var(--s4);
  border-top: 1px solid var(--rule-faint);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--s3);
}
.research__series-prog {
  display: flex;
  align-items: center;
  gap: var(--s3);
  flex: 1;
  min-width: 0;
}
.research__series-prog-bar {
  flex: 1;
  height: 2px;
  background: var(--rule-soft);
  border-radius: 1px;
  overflow: hidden;
  max-width: 160px;
}
.research__series-prog-fill {
  display: block;
  height: 100%;
  background: var(--ink);
}
.research__series-card.is-accent .research__series-prog-fill { background: var(--signal); }
.research__series-prog-text {
  font-family: var(--font-en);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ink-mute);
  white-space: nowrap;
}
.research__series-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12.5px;
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--signal);
  cursor: pointer;
  transition: gap 160ms ease;
  white-space: nowrap;
}
.research__series-cta:hover { gap: 10px; }

/* ============================================================
   최근 노트
   ============================================================ */
.research__notes {
  margin: 0;
}
.research__note {
  display: grid;
  grid-template-columns: 96px 1.4fr 2.4fr auto;
  align-items: baseline;
  gap: var(--s5);
  padding: var(--s4) var(--s3);
  border-bottom: 1px solid var(--rule-faint);
  width: 100%;
  text-align: left;
  cursor: pointer;
  transition: background 120ms ease, padding 160ms ease;
}
.research__note:hover { background: var(--paper-deep); padding-left: var(--s5); }
.research__note-date {
  font-family: var(--font-en);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--ink-dim);
  font-variant-numeric: tabular-nums;
}
.research__note-series {
  font-family: var(--font-cn);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-mute);
}
.research__note-title {
  font-size: 15px;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.005em;
}
.research__note-parts {
  font-family: var(--font-en);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ink-mute);
}

/* ============================================================
   라이선스 / 인용 안내
   ============================================================ */
.research__legal {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--s6);
}
.research__legal-col p {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--ink-soft);
  margin-top: var(--s3);
}

/* ============================================================
   반응형
   ============================================================ */
@media (max-width: 900px) {
  .research__series { grid-template-columns: 1fr; }
  .research__focus { grid-template-columns: 1fr; }
  .research__series-card { border-right: 0; }
  .research__legal { grid-template-columns: 1fr; gap: var(--s5); }
}
@media (max-width: 600px) {
  .research__hero-inner { padding: var(--s6) var(--s4); }
  .research__hero-meta { gap: var(--s5); }
  .research__inner { padding: var(--s6) var(--s4); }
  .research__focus { padding: var(--s5); }
  .research__section-head {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--s3);
  }
  .research__note {
    grid-template-columns: 1fr;
    gap: 4px;
    padding: var(--s4) var(--s2);
  }
  .research__note-series { font-size: 11px; }
  .research__note-parts { font-size: 10.5px; }
  .research__series-title { font-size: 20px; }
}