/* ============================================================
   KRDS UX Writing — Shared Stylesheet
   Used by: principles/, dictionary/, case-studies/
   ============================================================ */

/* ---- Tokens ---- */
:root {
  --font-sans: 'Pretendard GOV Variable','Pretendard Variable',system-ui,sans-serif;
  --accent: #256ef4;
  --bg: #ffffff; --bg-subtle: #f4f5f6; --bg-overlay: rgba(0,0,0,0.45);
  --border: #e6e8ea; --border-mid: #cdd1d5;
  --text: #1e2124; --text-mid: #464c53; --text-muted: #6d7882;
  --text-primary: var(--text);
  --text-secondary: var(--text-mid);
  --surface: var(--bg);
  --sidebar-w: 240px;
  --gnb-h: 56px;
}
[data-theme="dark"] {
  --bg: #131416; --bg-subtle: #1e2124;
  --border: #33363d; --border-mid: #464c53;
  --text: #ffffff; --text-mid: #cdd1d5; --text-muted: #8a949e;
  --accent: #6699ff;
}

/* ---- Reset ---- */
*,*::before,*::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--gnb-h) + 16px); }
body { font-family: var(--font-sans); background: var(--bg); color: var(--text); line-height: 1.7; -webkit-font-smoothing: antialiased; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---- Skip Nav ---- */
.skip-nav {
  position: absolute; top: -100%; left: 0;
  background: var(--accent); color: #fff;
  padding: 8px 16px; font-size: 14px; font-weight: 600; z-index: 9999;
}
.skip-nav:focus { top: 0; }

/* ---- GNB ---- */
.gnb {
  position: sticky; top: 0; z-index: 200;
  height: var(--gnb-h);
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center;
  padding: 0 24px; gap: 0;
}
.gnb-logo {
  font-size: 13px; font-weight: 700; color: var(--text);
  display: flex; align-items: center; gap: 8px;
  flex-shrink: 0; text-decoration: none;
  margin-right: 24px;
}
.gnb-logo:hover { text-decoration: none; }
.gnb-logo-mark {
  width: 24px; height: 24px; border-radius: 5px;
  background: var(--accent); color: #fff;
  font-size: 11px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}

/* Section nav */
.gnb-nav { display: flex; align-items: center; gap: 2px; flex: 1; }
.gnb-nav-link {
  font-size: 13px; font-weight: 500; color: var(--text-muted);
  padding: 6px 12px; border-radius: 6px;
  text-decoration: none; transition: color 0.15s, background 0.15s;
  white-space: nowrap;
}
.gnb-nav-link:hover { color: var(--text); background: var(--bg-subtle); text-decoration: none; }
.gnb-nav-link.active { color: var(--accent); font-weight: 700; background: rgba(37,110,244,0.06); }

/* GNB right actions */
.gnb-actions { display: flex; align-items: center; gap: 8px; margin-left: auto; flex-shrink: 0; }
.gnb-badge {
  font-size: 10px; font-weight: 700; letter-spacing: 0.04em;
  padding: 2px 8px; border-radius: 3px;
  border: 1px solid var(--border-mid); color: var(--text-muted);
}
.gnb-icon-btn {
  background: none; border: none; cursor: pointer;
  color: var(--text-muted); display: flex; align-items: center;
  padding: 6px; border-radius: 6px; transition: background 0.15s, color 0.15s;
}
.gnb-icon-btn:hover { background: var(--bg-subtle); color: var(--text); }

/* Hamburger (mobile only) */
.gnb-hamburger { display: none; }

/* ---- Page Layout ---- */
.page-layout {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  min-height: calc(100vh - var(--gnb-h));
}

/* ---- Sidebar / LNB ---- */
.sidebar {
  border-right: 1px solid var(--border);
  padding: 28px 0;
  position: sticky; top: var(--gnb-h);
  height: calc(100vh - var(--gnb-h));
  overflow-y: auto;
  background: var(--bg);
  z-index: 100;
}
.sidebar-section { margin-bottom: 8px; }
.sidebar-label {
  font-size: 10px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--text-muted); padding: 8px 20px 4px;
}
.sidebar-link {
  display: flex; align-items: center; gap: 6px;
  padding: 7px 20px; font-size: 13px; font-weight: 500;
  color: var(--text-mid); text-decoration: none;
  border-right: 2px solid transparent;
  transition: all 0.15s;
}
.sidebar-link:hover { color: var(--text); background: var(--bg-subtle); text-decoration: none; }
.sidebar-link.active {
  color: var(--accent); border-right-color: var(--accent);
  background: rgba(37,110,244,0.05); font-weight: 600;
}
.sidebar-link-badge {
  font-size: 10px; font-weight: 700; padding: 1px 6px; border-radius: 3px;
  background: var(--bg-subtle); color: var(--text-muted);
  border: 1px solid var(--border); margin-left: auto;
}
.sidebar-tag {
  font-size: 10px; font-weight: 600; padding: 1px 5px; border-radius: 3px;
  background: var(--bg-subtle); border: 1px solid var(--border);
  color: var(--text-muted); margin-left: auto;
}

/* ---- Content ---- */
.content { padding: 48px 56px 80px; }
.content-header { margin-bottom: 48px; padding-bottom: 32px; border-bottom: 1px solid var(--border); }
.content-eyebrow {
  font-size: 11px; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--accent); margin-bottom: 12px;
}
.content-title { font-size: 34px; font-weight: 800; letter-spacing: -0.03em; line-height: 1.2; margin-bottom: 12px; }
.content-headline { font-size: 20px; font-weight: 600; color: var(--text-mid); margin-bottom: 12px; letter-spacing: -0.01em; }
.content-desc { font-size: 15px; color: var(--text-muted); line-height: 1.8; max-width: 58ch; }
.content-cta {
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 14px; font-weight: 600; color: var(--accent);
  margin-top: 16px; text-decoration: none;
}
.content-cta:hover { text-decoration: underline; }

/* ---- Footer ---- */
.page-footer {
  border-top: 1px solid var(--border);
  padding: 32px 56px;
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 16px;
  font-size: 13px; color: var(--text-muted);
  grid-column: 1 / -1;
}
.footer-links { display: flex; gap: 16px; }
.footer-links a { color: var(--text-muted); font-size: 13px; }
.footer-links a:hover { color: var(--text); }

/* ---- Mobile overlay backdrop ---- */
.sidebar-backdrop {
  display: none;
  position: fixed; inset: 0;
  background: var(--bg-overlay);
  z-index: 150;
}
.sidebar-backdrop.open { display: block; }

/* ---- Responsive ---- */
@media (max-width: 900px) {
  .page-layout { grid-template-columns: 1fr; }
  .gnb-hamburger { display: flex; }
  .gnb-badge { display: none; }

  /* Sidebar becomes fixed overlay on mobile */
  .sidebar {
    position: fixed;
    top: 0; left: 0;
    width: min(var(--sidebar-w), 80vw);
    height: 100vh;
    transform: translateX(-110%);
    transition: transform 0.25s ease;
    box-shadow: 2px 0 24px rgba(0,0,0,0.12);
    padding-top: calc(var(--gnb-h) + 16px);
    z-index: 160;
  }
  .sidebar.open { transform: translateX(0); }

  .content { padding: 32px 20px 64px; }
  .page-footer { padding: 24px 20px; }
  .gnb-nav .gnb-nav-link { padding: 6px 8px; font-size: 12px; }
}

@media (max-width: 480px) {
  .gnb-nav { display: none; }
}

/* ---- LNB Accordion — principles pages ---- */
.lnb-tree { padding: 16px 0; }

.lnb-section-label {
  font-size: 10px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--text-muted); padding: 12px 20px 4px;
}
.lnb-section-label + .lnb-item { margin-top: 0; }
/* 두 번째 이후 섹션 레이블 앞에 시각 구분선 추가 */
.lnb-item + .lnb-section-label {
  margin-top: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.lnb-item-hd {
  display: flex; align-items: center;
  padding: 0 12px 0 16px; gap: 2px;
}
.lnb-item-a {
  display: flex; align-items: center; gap: 8px;
  flex: 1; padding: 7px 4px 7px 0;
  font-size: 13px; font-weight: 500; color: var(--text-mid);
  text-decoration: none; transition: color 0.15s; line-height: 1.3;
}
.lnb-item-a:hover { color: var(--text); text-decoration: none; }
.lnb-item-a.active { color: var(--accent); font-weight: 700; }


.lnb-tog {
  background: none; border: none; cursor: pointer;
  color: var(--text-muted); padding: 5px; border-radius: 4px;
  line-height: 0; flex-shrink: 0;
  transition: background 0.15s, color 0.15s;
}
.lnb-tog:hover { background: var(--bg-subtle); color: var(--text); }
.lnb-tog svg { transition: transform 0.2s ease; display: block; }
.lnb-item[aria-expanded="true"] > .lnb-item-hd > .lnb-tog svg { transform: rotate(90deg); }

.lnb-sub { padding: 2px 12px 6px 44px; }
.lnb-sub[hidden] { display: none; }
.lnb-sub-a {
  display: block; padding: 5px 8px;
  font-size: 12px; color: var(--text-muted);
  text-decoration: none; border-radius: 4px;
  transition: color 0.15s, background 0.15s;
}
.lnb-sub-a:hover { color: var(--text); background: var(--bg-subtle); text-decoration: none; }
.lnb-sub-a.active { color: var(--accent); font-weight: 600; }

.lnb-footer {
  padding: 12px 20px;
  border-top: 1px solid var(--border);
  margin-top: 8px;
  display: flex; flex-direction: column; gap: 2px;
}
.lnb-footer-a {
  display: block; padding: 6px 0;
  font-size: 12px; font-weight: 600; color: var(--text-muted);
  text-transform: uppercase; letter-spacing: 0.08em;
  text-decoration: none; transition: color 0.15s;
}
.lnb-footer-a:hover { color: var(--accent); text-decoration: none; }
.lnb-footer-a.active { color: var(--accent); }

/* ── 이터레이션 14: 섹션 레이블 ::before dot 아이콘 ── */
.lnb-section-label::before {
  content: '';
  display: inline-block;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--border-mid);
  margin-right: 6px;
  vertical-align: middle;
  margin-bottom: 1px;
}
/* 이터레이션 18: 섹션별 dot 색상 — data-label-section 기반 */
/* [A2] UX Designer 수정 — WCAG 1.4.11 비-텍스트 대비 3:1 준수 (opacity 제거) */
/* principle: #256ef4 → 4.53:1 / application: #8a5c00 → 5.36:1 / governance: #6b3fa0 → 7.3:1 */
.lnb-section-label[data-label-section="principle"]::before { background: var(--accent); }
.lnb-section-label[data-label-section="application"]::before { background: #8a5c00; }
.lnb-section-label[data-label-section="governance"]::before { background: #6b3fa0; }
[data-theme="dark"] .lnb-section-label[data-label-section="application"]::before { background: #c49c00; }
[data-theme="dark"] .lnb-section-label[data-label-section="governance"]::before { background: #a87ed6; }

/* ── 이터레이션 16: 컴포넌트 서브아이템 그룹 레이블 (UX Writer 확정 카피) ── */
.lnb-sub-group-label {
  font-size: 9px; font-weight: 700; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--text-muted);
  padding: 8px 8px 2px; display: block; opacity: 0.65;
  line-height: 1;
}
.lnb-sub-group-label:not(:first-child) {
  margin-top: 4px;
  border-top: 1px solid var(--border);
  padding-top: 8px;
}