/* ==================================================================
   백과사전 — 현대적인 자연과학 아카이브
   흰 바탕 · 산세리프 · 가는 선 · 여백 · 정렬
   카드도 그림자도 쓰지 않는다. 구분은 여백과 선과 타이포로 한다.
   ================================================================== */

:root {
  --ex-bg:       #ffffff;
  --ex-bg-soft:  #fafaf8;
  --ex-ink:      #1c1d1a;
  --ex-ink-2:    #55574f;
  --ex-ink-3:    #8e9186;
  --ex-line:     #e7e8e3;
  --ex-line-2:   #f1f2ee;
  --ex-accent:   #7d8760;   /* muted olive — 작은 곳에만 */
}

#codex {
  background: var(--ex-bg);
  background-image: none;
  color: var(--ex-ink);
  font-family: var(--font-ui);
  -webkit-font-smoothing: antialiased;
}
#codex::after { content: none; }   /* 종이 결 제거 */

.ex-page {
  max-width: 620px;
  margin: 0 auto;
  padding: calc(var(--safe-top) + 26px) 26px calc(var(--safe-bottom) + 108px);
  opacity: 0;
  transform: translateY(6px);
  transition: opacity .32s ease, transform .32s ease;
}
.ex-page.is-in { opacity: 1; transform: none; }

/* ---- 상단 뒤로 ---- */

.ex-back {
  display: flex; align-items: center; gap: 14px;
  margin: 0 0 30px; padding: 6px 2px;
  border: 0; background: none;
  font-family: inherit; font-size: 1.02rem; font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ex-ink);
  cursor: pointer;
}
.ex-back svg { width: 20px; height: 14px; flex: none; }

/* ---- 제목 ---- */

.ex-head { margin: 0 0 34px; }
.ex-rule {
  display: block; width: 26px; height: 2px;
  background: var(--ex-accent);
  margin-bottom: 18px;
}
.ex-kicker {
  margin: 0 0 10px;
  font-size: .72rem; letter-spacing: .22em;
  color: var(--ex-ink-3);
}
.ex-title {
  margin: 0;
  font-size: clamp(1.5rem, 6.6vw, 1.95rem);
  font-weight: 700; line-height: 1.32; letter-spacing: -.02em;
}
.ex-title--detail { font-size: clamp(1.75rem, 8vw, 2.3rem); margin-bottom: 12px; }
.ex-sub {
  margin: 12px 0 0;
  font-size: .92rem; line-height: 1.6;
  color: var(--ex-ink-3);
}
.ex-lead {
  margin: 0 0 6px;
  font-size: 1rem; line-height: 1.75;
  color: var(--ex-ink-2);
}
.ex-crumb {
  margin: 0 0 22px;
  font-size: .8rem; letter-spacing: .04em;
  color: var(--ex-ink-3);
}
.ex-crumb span { margin: 0 6px; color: var(--ex-line); }

/* ---- 홈: 박물관 인덱스 블록 ---- */

.ex-blocks { display: grid; gap: 12px; margin-bottom: 46px; }

.ex-block {
  position: relative;
  display: grid;
  grid-template-columns: 112px 1fr auto;
  align-items: center;
  gap: 14px;
  width: 100%;
  padding: 20px 18px;
  border: 1px solid var(--ex-line);
  border-radius: 2px;
  background: var(--ex-bg-soft);
  font-family: inherit;
  text-align: left;
  cursor: pointer;
  transition: border-color .25s ease;
}
.ex-block:hover { border-color: #d8dad2; }
.ex-block-no {
  position: absolute; top: 12px; right: 16px;
  font-size: .72rem; letter-spacing: .12em; color: var(--ex-ink-3);
}
.ex-block-art {
  display: flex; align-items: center; justify-content: center;
  height: 74px; overflow: hidden;
}
.ex-block-img { display: block; width: 100%; }
.ex-block-art img, .ex-block-art svg {
  max-width: 100%; max-height: 100%;
  filter: saturate(.18) contrast(1.02);
}
.ex-block-text {
  display: block;
  padding-left: 18px;
  border-left: 1px solid var(--ex-line);
}
.ex-block-kicker {
  display: block; margin-bottom: 6px;
  font-size: .74rem; letter-spacing: .1em; color: var(--ex-ink-3);
}
.ex-block-name {
  display: block;
  font-size: 1.32rem; font-weight: 700; letter-spacing: -.02em;
}
.ex-block-count {
  display: block; margin-top: 8px;
  font-size: .86rem; color: var(--ex-ink-3); letter-spacing: .04em;
}
.ex-block > .ex-arrow { color: var(--ex-ink-2); }

/* ---- 구역 ---- */

.ex-section { margin: 0 0 40px; }
.ex-section--ruled { border-top: 1px solid var(--ex-line); padding-top: 30px; }
.ex-section-head {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 12px;
}
.ex-section-title {
  margin: 0 0 4px;
  font-size: 1.02rem; font-weight: 700; letter-spacing: -.01em;
}
.ex-section-title--gap { margin-top: 44px; }
.ex-section-note { font-size: .78rem; color: var(--ex-ink-3); }

/* ---- 질문 줄 ---- */

.ex-list { list-style: none; margin: 14px 0 0; padding: 0; }

.ex-row {
  display: grid;
  grid-template-columns: 62px 1fr 24px;
  align-items: center;
  gap: 16px;
  padding: 17px 2px;
  border-top: 1px solid var(--ex-line-2);
  cursor: pointer;
  color: var(--ex-ink-3);
}
.ex-list .ex-row:last-child { border-bottom: 1px solid var(--ex-line-2); }
.ex-row-title {
  margin: 0;
  font-size: .96rem; line-height: 1.5; font-weight: 500;
  color: var(--ex-ink);
}
.ex-thumb {
  display: flex; align-items: center; justify-content: center;
  height: 44px; overflow: hidden;
}
.ex-thumb-img {
  max-width: 100%; max-height: 100%;
  display: block;
  filter: saturate(.16) contrast(1.03);
}
.ex-row-lock { display: flex; justify-content: center; color: var(--ex-ink-3); }
.ex-row.is-locked { cursor: default; }
.ex-row.is-locked .ex-row-title { color: var(--ex-ink-3); font-weight: 400; }
.ex-row.is-locked .ex-arrow { opacity: .35; }

.ex-arrow { width: 24px; height: 12px; flex: none; }
.ex-lock  { width: 15px; height: 17px; }

/* ---- 목록 항목 (세계 · 원리) ---- */

.ex-entries { list-style: none; margin: 26px 0 0; padding: 0; }

.ex-entry {
  display: grid;
  grid-template-columns: 108px 1fr 24px;
  align-items: center;
  gap: 18px;
  padding: 22px 2px;
  border-top: 1px solid var(--ex-line);
  cursor: pointer;
  color: var(--ex-ink-2);
}
.ex-entries .ex-entry:last-child { border-bottom: 1px solid var(--ex-line); }
.ex-entry-art {
  display: flex; align-items: center; justify-content: center;
  height: 84px; overflow: hidden;
}
.ex-entry-art svg, .ex-entry-art img {
  max-width: 100%; max-height: 100%;
  filter: saturate(.16) contrast(1.03);
}
.ex-entry-text { display: block; min-width: 0; }
.ex-entry-name {
  display: flex; align-items: center; gap: 8px;
  font-size: 1.22rem; font-weight: 700; letter-spacing: -.02em;
  color: var(--ex-ink);
}
.ex-entry-lead {
  display: block; margin-top: 7px;
  font-size: .89rem; line-height: 1.55; color: var(--ex-ink-3);
}
.ex-entry-meta {
  display: block; margin-top: 12px;
  font-size: .82rem; letter-spacing: .04em; color: var(--ex-ink-3);
}
.ex-entry.is-locked { cursor: default; }
.ex-entry.is-locked .ex-entry-name { color: var(--ex-ink-2); }
.ex-entry.is-locked .ex-entry-art { opacity: .5; }
.ex-entry.is-locked .ex-arrow { opacity: .3; }

/* ---- 연결된 원리 ---- */

.ex-links { list-style: none; margin: 14px 0 0; padding: 0; }
.ex-links li {
  display: flex; align-items: center; justify-content: space-between;
  gap: 14px;
  padding: 15px 2px;
  border-top: 1px solid var(--ex-line-2);
  font-size: 1rem; font-weight: 500;
  color: var(--ex-ink);
  cursor: pointer;
}
.ex-links li:last-child { border-bottom: 1px solid var(--ex-line-2); }
.ex-links .ex-arrow { color: var(--ex-ink-3); }

/* ---- 세계 상세의 큰 그림 ---- */

.ex-hero {
  display: flex; align-items: center; justify-content: center;
  margin: 0 0 26px;
  padding: 22px 18px;
  min-height: 170px;
  border: 1px solid var(--ex-line);
  background: var(--ex-bg-soft);
}
.ex-hero img {
  max-width: 78%; max-height: 190px; display: block;
  filter: saturate(.18) contrast(1.03);
}

/* ---- 원리 상세: 관계 ---- */

.ex-web {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px 18px;
  margin: 10px 0 42px;
}

/* 관계를 잇는 선. 가는 선과 점만 쓴다. */
.ex-rel { position: relative; padding-top: 16px; }
.ex-rel[role="button"] { cursor: pointer; }

.ex-rel::before, .ex-rel::after {
  content: ''; position: absolute;
  background: var(--ex-accent);
  opacity: .42;
}
.ex-rel-dot {
  position: absolute;
  width: 5px; height: 5px; border-radius: 50%;
  background: var(--ex-accent);
}

/* 위 두 칸: 점 → 가로 → 세로로 내려가 가운데에서 멎는다 */
.ex-rel.is-tl::before, .ex-rel.is-tr::before { top: 2px; height: 1px; }
.ex-rel.is-tl::after,  .ex-rel.is-tr::after  { top: 2px; bottom: -26px; width: 1px; }
.ex-rel.is-tl::before { left: 6px; right: 18%; }
.ex-rel.is-tl::after  { right: 18%; }
.ex-rel.is-tr::before { right: 6px; left: 18%; }
.ex-rel.is-tr::after  { left: 18%; }
.ex-rel.is-tl .ex-rel-dot { left: 0; top: 0; }
.ex-rel.is-tr .ex-rel-dot { right: 0; top: 0; }

/* 아래 두 칸: 거울상 */
.ex-rel.is-bl, .ex-rel.is-br { padding-top: 0; padding-bottom: 16px; }
.ex-rel.is-bl::before, .ex-rel.is-br::before { bottom: 2px; height: 1px; }
.ex-rel.is-bl::after,  .ex-rel.is-br::after  { bottom: 2px; top: -12px; width: 1px; }
.ex-rel.is-bl::before { left: 6px; right: 18%; }
.ex-rel.is-bl::after  { right: 18%; }
.ex-rel.is-br::before { right: 6px; left: 18%; }
.ex-rel.is-br::after  { left: 18%; }
.ex-rel.is-bl .ex-rel-dot { left: 0; bottom: 0; }
.ex-rel.is-br .ex-rel-dot { right: 0; bottom: 0; }

.ex-rel.is-tr, .ex-rel.is-br { text-align: right; }

.ex-rel-kicker {
  margin: 0 0 8px;
  font-size: .78rem; letter-spacing: .02em; color: var(--ex-ink-3);
}
.ex-rel-body {
  margin: 0;
  font-size: .98rem; line-height: 1.5; font-weight: 700;
  letter-spacing: -.015em; color: var(--ex-ink);
}
.ex-rel .ex-arrow { margin-top: 10px; color: var(--ex-ink-2); }
.ex-rel.is-tr .ex-arrow, .ex-rel.is-br .ex-arrow { margin-left: auto; display: block; }

.ex-web-center {
  grid-column: 1 / -1;
  display: flex; flex-direction: column; align-items: center;
  padding: 6px 0 2px;
}
.ex-web-center .mark { width: 100%; max-width: 230px; height: auto; display: block; }
.ex-web-name {
  margin: 4px 0 0;
  font-size: 1.18rem; font-weight: 700; letter-spacing: -.01em;
}
.ex-web-en {
  margin: 5px 0 0;
  font-size: .72rem; letter-spacing: .2em; color: var(--ex-ink-3);
}

/* ---- 글 ---- */

.ex-article .article-title { margin-top: 0; }

/* ==================================================================
   글 — 백과사전 안에서도, 문제를 푼 직후에도 같은 조판을 쓴다
   ================================================================== */

.article-rel {
  display: flex; align-items: baseline; justify-content: flex-end;
  flex-wrap: wrap; gap: 8px;
  margin: 0 0 14px;
  font-size: .8rem; line-height: 1.5;
  color: var(--ex-ink-2);
  text-align: right;
}
.article-rel b { font-weight: 700; color: var(--ex-accent); }
.article-rel span { color: var(--ex-line); }

.article-plate {
  margin: 0 0 30px;
  padding: 16px 14px;
  border: 1px solid var(--ex-line);
  background: var(--ex-bg-soft);
}
.article-plate svg { display: block; width: 100%; height: auto; filter: saturate(.2) contrast(1.02); }

.article-title {
  margin: 0 0 18px;
  font-family: var(--font-ui);
  font-size: clamp(1.52rem, 6.6vw, 2rem);
  font-weight: 700; line-height: 1.38; letter-spacing: -.025em;
  color: var(--ex-ink);
}

.article-concept {
  margin: 0;
  font-size: 1rem; font-weight: 500; letter-spacing: -.01em;
  color: var(--ex-ink-2);
}
.article-concept-en {
  margin: 5px 0 16px;
  font-size: .76rem; letter-spacing: .2em;
  text-transform: uppercase; color: var(--ex-ink-3);
}

.article-rule {
  height: 1px; background: var(--ex-line);
  margin: 26px 0 32px;
}

.article-h {
  margin: 2.7rem 0 1.15rem;
  font-family: var(--font-ui);
  font-size: 1.08rem; font-weight: 700;
  line-height: 1.5; letter-spacing: -.02em;
  color: var(--ex-ink);
}
.article-body > .article-h:first-child { margin-top: 0; }
.article-body strong { font-weight: 700; color: #121310; }

.article-body p {
  margin: 0 0 1.55rem;
  font-family: var(--font-ui);
  font-size: clamp(1rem, 4.2vw, 1.06rem);
  line-height: 1.92;
  letter-spacing: -.005em;
  color: #262723;
  user-select: text; -webkit-user-select: text;
}

/* ---- 만든 사람 ---- */

.ex-made {
  display: flex; align-items: center; justify-content: center;
  gap: 14px;
  margin-top: 54px;
  padding-top: 28px;
  border-top: 1px solid var(--ex-line-2);
}
.ex-made-by {
  font-size: .82rem; font-weight: 500; letter-spacing: -.01em;
  color: var(--ex-ink-3);
}
.ex-made-home {
  display: flex; align-items: center; justify-content: center;
  width: 38px; height: 38px;
  border: 1px solid var(--ex-line);
  border-radius: 10px;
  color: var(--ex-ink-2);
  transition: border-color .25s ease, color .25s ease;
}
.ex-made-home:hover { border-color: var(--ex-accent); color: var(--ex-accent); }
.ex-made-home svg { width: 20px; height: 20px; }