/* =====================================================================
   Layout — 헤더 · 모바일 메뉴 · 섹션 띠 · 4단 그리드 · 푸터
   ===================================================================== */

/* ---------- 공통 페이지의 뷰포트 높이 ------------------------------- */
body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}
body > .site-header,
body > .site-footer { flex-shrink: 0; }
body > main { flex: 1; }

/* ---------- 헤더 (Figma Nav/Header · Nav/Header M) ------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: var(--c-paper);
  border-bottom: var(--line) solid var(--c-line);
}
.site-header__inner {
  display: grid;
  grid-template-columns: 25% repeat(4, 1fr);   /* 360 + 270 × 4 */
  height: 100%;
}
.site-header__brand,
.site-header__tab {
  display: flex;
  align-items: center;
  height: 100%;
  border-right: var(--line) solid var(--c-line);
}
.site-header__brand { padding-left: var(--gutter); }
.site-header__tab   { justify-content: center; transition: background-color .2s, color .2s; }
.site-header__tab:last-child { border-right: 0; }
.site-header__tab:hover { background: var(--c-accent-soft); }
.site-header__tab[aria-current="page"] { background: var(--c-accent); color: var(--c-on-accent); }
.site-header__menu-btn { display: none; }

/* 2×2 격자 메뉴 아이콘 — 열리면 대각선 2칸 */
.menu-icon { position: relative; width: 16px; height: 16px; }
.menu-icon i { position: absolute; width: 6px; height: 6px; background: var(--c-ink); transition: opacity .2s; }
.menu-icon i:nth-child(1) { left: 0;  top: 0; }
.menu-icon i:nth-child(2) { right: 0; top: 0; }
.menu-icon i:nth-child(3) { left: 0;  bottom: 0; }
.menu-icon i:nth-child(4) { right: 0; bottom: 0; }
.is-menu-open .menu-icon i:nth-child(2),
.is-menu-open .menu-icon i:nth-child(3) { opacity: 0; }

/* 모바일 메뉴 (Figma Nav/Menu M) */
.mobile-menu {
  position: fixed;
  inset: var(--header-h) 0 auto 0;
  z-index: 49;
  background: var(--c-paper);
  border-bottom: var(--line) solid var(--c-line);
  transform: translateY(-8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity .2s, transform .2s, visibility .2s;
}
.is-menu-open .mobile-menu { opacity: 1; visibility: visible; transform: none; }
.mobile-menu__item {
  display: flex; align-items: center; gap: 16px;
  height: 64px; padding-left: 16px;
  border-bottom: var(--line) solid var(--c-line);
}
.mobile-menu__item[aria-current="page"] { background: var(--c-accent); color: var(--c-on-accent); }
.mobile-menu__item .t-label-en { color: var(--c-accent-text); }
.mobile-menu__item[aria-current="page"] .t-label-en { color: var(--c-on-accent); }
.mobile-menu__foot { padding: 16px 16px 24px; display: grid; gap: 4px; }
.menu-dim {
  position: fixed; inset: var(--header-h) 0 0 0; z-index: 48;
  background: var(--c-ink); opacity: 0; visibility: hidden; transition: opacity .2s, visibility .2s;
}
.is-menu-open .menu-dim { opacity: .4; visibility: visible; }

/* ---------- 섹션 띠 (Figma Section/Divider) ------------------------ */
.divider {
  position: relative;
  height: var(--divider-h);
  background: var(--c-hero);
  color: var(--c-on-hero);
  display: grid;
  grid-template-columns: 25% 1fr;
  overflow: hidden;
}
.divider::before { /* 4단 세로선 + 가운데 가로선 */
  content: "";
  position: absolute; inset: 0;
  pointer-events: none;
  background:
    linear-gradient(to right, transparent calc(25% - 1px), var(--c-on-hero) calc(25% - 1px), var(--c-on-hero) 25%, transparent 25%),
    linear-gradient(to right, transparent calc(50% - 1px), var(--c-on-hero) calc(50% - 1px), var(--c-on-hero) 50%, transparent 50%),
    linear-gradient(to right, transparent calc(75% - 1px), var(--c-on-hero) calc(75% - 1px), var(--c-on-hero) 75%, transparent 75%),
    linear-gradient(to bottom, transparent calc(50% - 1px), var(--c-on-hero) calc(50% - 1px), var(--c-on-hero) 50%, transparent 50%);
  opacity: .35;
}
.divider__no, .divider__title { position: relative; padding: 18px var(--gutter); }

/* ---------- 4단 그리드 (선은 gap으로 그립니다) ---------------------- */
.grid {
  display: grid;
  grid-template-columns: repeat(var(--grid-cols), minmax(0, 1fr));
  gap: var(--line);
  background: var(--c-line);
  border-bottom: var(--line) solid var(--c-line);
}
.grid > * { background: var(--c-paper); min-width: 0; }
.cell { padding: var(--gutter); }
.span-2 { grid-column: span 2; }
.span-3 { grid-column: span 3; }
.span-4 { grid-column: 1 / -1; }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }   /* 6개원 소개 */
.cell--filler { padding: 0; }                                    /* 줄 끝 빈 칸 */

.block-head {                       /* 목록 · 블록 머리줄 */
  display: grid;
  grid-template-columns: 25% 1fr;
  align-items: baseline;
  padding: 24px var(--gutter) 16px;
  border-bottom: var(--line) solid var(--c-line);
}
.block-head .t-caption { color: var(--c-muted); }
.block-head__intro { max-width: 760px; color: var(--c-ink); }

/* ---------- 푸터 (Figma Nav/Footer) -------------------------------- */
.site-footer {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-top: var(--line) solid var(--c-line);
}
.site-footer > div { padding: 20px var(--gutter) 28px; border-right: var(--line) solid var(--c-line); white-space: pre-line; }
.site-footer > div:last-child { border-right: 0; }

/* ---------- 반응형 -------------------------------------------------- */
@media (max-width: 1024px) {
  .span-3 { grid-column: span 2; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .block-head { grid-template-columns: 1fr; gap: 4px; }
}
@media (max-width: 640px) {
  .site-header__inner { grid-template-columns: var(--header-h) 1fr var(--header-h); }
  .site-header__tab { display: none; }
  .site-header__menu-btn {
    display: flex; align-items: center; justify-content: center;
    width: var(--header-h); height: 100%;
    border-right: var(--line) solid var(--c-line);
  }
  .is-menu-open .site-header__menu-btn { background: var(--c-accent); }
  .site-header__brand { justify-content: center; padding: 0; border-right: 0; }
  .site-header__inner::after { content: ""; }

  .divider { grid-template-columns: 25% 1fr; }
  .divider__no, .divider__title { padding: 14px 16px; }

  .span-2, .span-3, .span-4 { grid-column: auto; }
  .grid--3 { grid-template-columns: 1fr; }
  .cell--filler { display: none; }

  .site-footer { grid-template-columns: 1fr; padding: 24px 16px 32px; gap: 16px; }
  .site-footer > div { padding: 0; border: 0; }
}
@media (min-width: 641px) {
  .mobile-menu, .menu-dim { display: none; }
}