/* ============ Karma Docs — Bright Theme ============ */
:root {
  --bg:            #f6f8fc;
  --bg-card:       #ffffff;
  --sidebar:       #ffffff;
  --ink:           #1f2937;
  --ink-soft:      #4b5563;
  --ink-faint:     #9ca3af;
  --primary:       #4f6ef7;
  --primary-soft:  #eef2ff;
  --primary-deep:  #3b53d4;
  --accent:        #14b8a6;
  --accent-soft:   #e6fbf7;
  --border:        #e6eaf2;
  --code-bg:       #f3f5fa;
  --shadow:        0 1px 3px rgba(31,41,55,.06), 0 8px 24px rgba(31,41,55,.06);
  --radius:        14px;
  --sidebar-w:     317px;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Apple SD Gothic Neo",
               "Noto Sans KR", "Malgun Gothic", Roboto, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Layout ---------- */
.layout { display: flex; min-height: 100vh; }

/* ---------- Sidebar ---------- */
.sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  background: var(--sidebar);
  border-right: 1px solid var(--border);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  padding: 22px 16px 40px;
}
.brand { display: flex; align-items: center; gap: 12px; padding: 4px 8px 18px; cursor: pointer; border-radius: 10px; transition: background .12s; }
.brand:hover { background: linear-gradient(135deg, #f3f6ff, #eefbf8); }
.brand .logo {
  width: 40px; height: 40px; border-radius: 11px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: grid; place-items: center; color: #fff; font-size: 20px; font-weight: 800;
  box-shadow: 0 6px 16px rgba(79,110,247,.32);
}
.brand .title { font-size: 16px; font-weight: 800; letter-spacing: -.2px; white-space: nowrap; }
.brand .subtitle { font-size: 11.5px; color: var(--ink-faint); margin-top: 1px; }
.version-badge {
  display: inline-block; font-size: 10.5px; font-weight: 700; vertical-align: middle;
  color: var(--primary-deep); background: var(--primary-soft); border: 1px solid #dfe5ff;
  padding: 1px 7px; border-radius: 999px; margin-left: 4px; letter-spacing: .02em;
}

.search {
  width: 100%; padding: 10px 12px; margin: 4px 0 16px;
  border: 1px solid var(--border); border-radius: 10px;
  background: var(--bg); font-size: 13.5px; color: var(--ink); outline: none;
  transition: border-color .15s, box-shadow .15s;
}
.search:focus { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }

/* 섹션(대분류) 사이: 가장 굵은 구분선 */
.nav-section { margin-bottom: 8px; }
.nav-section + .nav-section { border-top: 3px solid #aab4ca; padding-top: 14px; margin-top: 12px; }
.sec-title {
  font-size: 12.5px; font-weight: 800; letter-spacing: .02em;
  color: var(--primary-deep); margin: 0 2px 8px; padding: 7px 12px;
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
  border: 1px solid #e3e8f6; border-radius: 9px;
}
.nav-group { margin-bottom: 12px; }
/* 그룹(중분류) 사이: 중간 굵기 구분선 */
.nav-group + .nav-group { border-top: 1.5px solid #dde3ee; padding-top: 11px; }
.nav-group h4 {
  font-size: 11px; text-transform: uppercase; letter-spacing: .08em;
  color: var(--ink-faint); margin: 2px 10px 7px; font-weight: 700;
}
.nav-item {
  display: flex; align-items: center; gap: 11px;
  padding: 10px 12px; margin: 2px 0; border-radius: 10px;
  font-size: 15px; color: var(--ink-soft); cursor: pointer;
  border: 1px solid transparent; transition: background .12s, color .12s;
  user-select: none;
}
.nav-item .ico {
  width: 19px; height: 19px; flex: 0 0 19px;
  stroke-width: 2.1; color: var(--ico, var(--ink-faint));   /* 그룹별 옅은 색 */
  transition: transform .12s, filter .12s;
}
.nav-item:hover .ico { transform: scale(1.1); filter: saturate(1.3); }
.nav-item.active .ico { filter: saturate(1.35) brightness(.95); }
/* 항목 사이: 작은(얇은) 구분선 */
.nav-item + .nav-item { border-top: 1px solid #eef1f7; }
.nav-item:hover {
  background: linear-gradient(135deg, #f3f6ff, #eefbf8);
  color: var(--ink); border-color: #eaeef8;
}
.nav-item.active {
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
  color: var(--primary-deep); border-color: #dfe5ff; font-weight: 700;
  box-shadow: 0 2px 8px rgba(79,110,247,.10);
}
.nav-item.hidden { display: none; }

/* 로그인 사용자 칩 */
.user-chip {
  display: flex; align-items: center; gap: 8px; margin: 14px 2px 4px; padding: 9px 11px;
  border: 1px solid var(--border); border-radius: 10px;
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
  font-size: 12.5px; color: var(--ink-soft);
}
.user-chip .ico { width: 18px; height: 18px; flex: 0 0 18px; color: var(--primary-deep); }
.user-chip .uc-email { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-weight: 600; color: var(--ink); }
.user-chip .uc-out { flex: 0 0 auto; color: var(--ink-faint); display: inline-flex; }
.user-chip .uc-out:hover { color: #dc2626; }
.user-chip .uc-out svg { width: 16px; height: 16px; }

/* ---------- Main ---------- */
.main { flex: 1 1 auto; min-width: 0; display: flex; flex-direction: column; }
.topbar {
  display: none; align-items: center; gap: 12px;
  padding: 12px 16px; background: var(--bg-card);
  border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 20;
}
.hamburger {
  width: 38px; height: 38px; border-radius: 10px; border: 1px solid var(--border);
  background: #fff; font-size: 18px; cursor: pointer; display: grid; place-items: center;
}
.content-wrap {
  padding: 40px clamp(20px, 4vw, 56px) 96px; width: 100%;
  margin-inline: auto; max-width: 2600px;            /* 넓게 (기본 토글 ON) */
  transition: max-width .42s cubic-bezier(.22,.61,.36,1);
}
/* 노션식(좁게) 모드 — 폭만 바뀌고 항상 중앙정렬이라 부드럽게 전환됨 */
body.narrow .content-wrap { max-width: 920px; }

/* 본문 폭 토글 스위치 */
.layout-toggle {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  margin: 0 2px 16px; padding: 8px 12px; border: 1px solid var(--border);
  border-radius: 10px; background: var(--bg);
}
.lt-label { font-size: 12.5px; color: var(--ink-soft); font-weight: 600; }
.switch { position: relative; display: inline-block; width: 40px; height: 22px; flex: 0 0 auto; }
.switch input { opacity: 0; width: 0; height: 0; }
.switch .slider { position: absolute; inset: 0; background: #cbd5e1; border-radius: 999px; transition: background .2s; cursor: pointer; }
.switch .slider::before {
  content: ""; position: absolute; height: 16px; width: 16px; left: 3px; top: 3px;
  background: #fff; border-radius: 50%; transition: transform .2s; box-shadow: 0 1px 3px rgba(0,0,0,.25);
}
.switch input:checked + .slider { background: var(--primary); }
.switch input:checked + .slider::before { transform: translateX(18px); }

/* progress / loading */
.loading { color: var(--ink-faint); font-size: 14px; padding: 40px 0; }
.error-box {
  background: #fff7ed; border: 1px solid #fed7aa; color: #9a3412;
  padding: 18px 20px; border-radius: var(--radius); font-size: 14px;
}
.error-box code { background: #ffedd5; padding: 2px 6px; border-radius: 6px; }

/* ---------- 메인(홈) 페이지 ---------- */
.home { animation: fade .32s cubic-bezier(.22,.61,.36,1); }
.home-hero {
  text-align: center; padding: 28px 20px 36px; border-radius: var(--radius);
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
  border: 1px solid #e3e8f6; box-shadow: var(--shadow); margin-bottom: 26px;
}
.home-logo {
  width: 72px; height: 72px; border-radius: 18px; margin: 0 auto 16px; display: grid; place-items: center;
  color: #fff; font-size: 40px; font-weight: 900;
  background: linear-gradient(135deg, var(--primary), var(--accent)); box-shadow: 0 10px 24px rgba(79,110,247,.32);
}
.home-hero h1 { font-size: 30px; font-weight: 800; margin: 0 0 8px; letter-spacing: -.5px; color: var(--ink); }
.home-ver {
  font-size: 12px; font-weight: 700; vertical-align: middle; color: var(--primary-deep);
  background: #fff; border: 1px solid #dfe5ff; padding: 2px 9px; border-radius: 999px; margin-left: 4px;
}
.home-hero p { color: var(--ink-soft); font-size: 14.5px; margin: 0 0 22px; }
.home-actions { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.home-btn {
  display: inline-flex; align-items: center; gap: 7px; padding: 10px 18px; border-radius: 11px;
  background: #fff; border: 1px solid var(--border); color: var(--ink); font-weight: 700; font-size: 14px;
  text-decoration: none; cursor: pointer; transition: transform .12s, box-shadow .12s, border-color .12s;
}
.home-btn:hover { transform: translateY(-2px); box-shadow: var(--shadow); border-color: var(--primary); }
.home-btn.primary { background: linear-gradient(135deg, var(--primary), var(--primary-deep)); color: #fff; border-color: transparent; box-shadow: 0 6px 16px rgba(79,110,247,.28); }
.home-btn i { width: 17px; height: 17px; }

.home-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; }
.home-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px 18px 14px; box-shadow: var(--shadow);
}
.home-card h3 {
  font-size: 14px; font-weight: 800; margin: 0 0 12px; color: var(--primary-deep);
  display: flex; align-items: center; gap: 7px;
}
.home-card h3::before { content: ""; width: 4px; height: 15px; border-radius: 3px; background: linear-gradient(var(--primary), var(--accent)); }
.home-links { display: flex; flex-direction: column; gap: 2px; }
.home-links a {
  display: flex; align-items: center; gap: 9px; padding: 7px 9px; border-radius: 8px;
  color: var(--ink-soft); text-decoration: none; font-size: 13.5px; transition: background .12s, color .12s;
}
.home-links a:hover { background: linear-gradient(135deg, #f3f6ff, #eefbf8); color: var(--ink); }
.home-links a i { width: 16px; height: 16px; flex: 0 0 16px; color: var(--ink-faint); }
.home-links a:hover i { color: var(--primary); }
#content[data-doc="home"] .page-nav { display: none; }
.pn-ico { width: 15px; height: 15px; vertical-align: -2px; margin-right: 4px; color: var(--primary); }

/* ---------- Markdown content ---------- */
.md { animation: fade .32s cubic-bezier(.22,.61,.36,1); }
@keyframes fade { from { opacity: 0; transform: translateY(10px);} to {opacity:1; transform:none;} }

/* 접이식 토글(details) — API 레퍼런스 등 */
.md details {
  border: 1px solid var(--border); border-radius: 12px; margin: 12px 0; overflow: hidden;
  background: var(--bg-card); box-shadow: var(--shadow); transition: box-shadow .15s;
}
.md details[open] { box-shadow: 0 6px 22px rgba(79,110,247,.14); }
.md summary {
  cursor: pointer; padding: 13px 16px; font-weight: 700; color: var(--ink);
  list-style: none; display: flex; align-items: center; gap: 9px; user-select: none;
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
}
.md summary::-webkit-details-marker { display: none; }
.md summary::before { content: "▶"; color: var(--primary-deep); font-size: 11px; transition: transform .2s ease; }
.md details[open] summary::before { transform: rotate(90deg); }
.md summary:hover { filter: brightness(.97); }
.md details[open] summary { border-bottom: 1px solid var(--border); }
.md details .table-wrap { margin: 12px 14px; }
.md details > p, .md details > ul, .md details > ol { margin-left: 16px; margin-right: 16px; }

/* 콘텐츠 인라인 아이콘(이모지 대체) */
.md-ico {
  display: inline-block; width: 1.05em; height: 1.05em; vertical-align: -0.16em;
  stroke-width: 2.2; color: var(--primary); margin-right: .22em; flex: 0 0 auto;
}
.md h1 .md-ico, .md h2 .md-ico { color: var(--primary-deep); }
.md summary .md-ico { color: var(--primary-deep); margin-right: .1em; }
.md blockquote .md-ico { color: var(--primary-deep); }

.md h1 {
  font-size: 30px; font-weight: 800; letter-spacing: -.5px; margin: 0 0 18px;
  padding-bottom: 14px; border-bottom: 2px solid var(--border); line-height: 1.25;
}
.md h2 {
  font-size: 21px; font-weight: 800; margin: 38px 0 14px; letter-spacing: -.3px;
  display: flex; align-items: center; gap: 8px;
}
.md h2::before {
  content: ""; width: 4px; height: 20px; border-radius: 3px;
  background: linear-gradient(var(--primary), var(--accent));
}
.md h3 { font-size: 16.5px; font-weight: 700; margin: 26px 0 10px; color: var(--ink); }
.md p { margin: 12px 0; color: var(--ink-soft); }
.md a { color: var(--primary-deep); text-decoration: none; border-bottom: 1px solid #c7d0fb; }
.md a:hover { background: var(--primary-soft); }
.md strong { color: var(--ink); font-weight: 700; }
.md ul, .md ol { padding-left: 22px; color: var(--ink-soft); }
.md li { margin: 5px 0; }
.md hr { border: none; border-top: 1px solid var(--border); margin: 30px 0; }
.md img { max-width: 100%; height: auto; border-radius: 10px; border: 1px solid var(--border); margin: 10px 0; box-shadow: var(--shadow); }

/* blockquote / callout */
.md blockquote {
  margin: 18px 0; padding: 14px 18px;
  background: var(--primary-soft); border-left: 4px solid var(--primary);
  border-radius: 10px; color: var(--ink-soft);
}
.md blockquote p { margin: 6px 0; }
.md blockquote strong { color: var(--primary-deep); }

/* inline + block code */
.md code {
  font-family: "SF Mono", "JetBrains Mono", "Fira Code", ui-monospace, Menlo, Consolas, monospace;
  font-size: 13px; background: var(--code-bg); padding: 2px 6px; border-radius: 6px; color: #b5306e;
}
.md pre {
  background: #0f172a; color: #e2e8f0; padding: 18px 20px; border-radius: var(--radius);
  overflow-x: auto; margin: 16px 0; font-size: 13px; line-height: 1.6;
  box-shadow: var(--shadow);
}
.md pre code { background: none; color: inherit; padding: 0; font-size: 13px; }

/* tables */
.md .table-wrap { margin: 18px 0; overflow-x: auto; border-radius: var(--radius); box-shadow: var(--shadow); }
.md .table-wrap::-webkit-scrollbar { height: 8px; }
.md .table-wrap::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 8px; }
.md table {
  border-collapse: collapse; width: 100%; margin: 0; font-size: 13.5px;
  background: var(--bg-card); overflow: hidden; display: table;
}
.md thead { background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft)); }
.md th { text-align: left; padding: 11px 14px; font-weight: 700; color: var(--ink); }
.md td { padding: 10px 14px; border-top: 1px solid var(--border); color: var(--ink-soft); }
.md tbody tr:hover { background: var(--bg); }

/* 영상 링크 카드 */
.video-card {
  display: flex; align-items: center; gap: 16px; margin: 20px 0;
  padding: 16px 20px; border-radius: var(--radius);
  background: linear-gradient(135deg, #eef2ff, #e6fbf7);
  border: 1px solid #dfe5ff; box-shadow: var(--shadow);
}
.video-ico {
  flex: 0 0 48px; width: 48px; height: 48px; border-radius: 12px;
  display: grid; place-items: center; font-size: 24px;
  background: #fff; box-shadow: 0 4px 12px rgba(79,110,247,.18);
}
.video-meta { flex: 1; min-width: 0; }
.video-title { font-weight: 800; color: var(--ink); font-size: 15.5px; }
.video-sub { font-size: 12.5px; color: var(--ink-soft); margin-top: 2px; }
.video-link {
  flex: 0 0 auto; text-decoration: none; white-space: nowrap;
  background: linear-gradient(135deg, var(--primary), var(--primary-deep));
  color: #fff !important; font-weight: 700; font-size: 14px;
  padding: 10px 18px; border-radius: 10px; border: none !important;
  box-shadow: 0 6px 16px rgba(79,110,247,.28); transition: transform .12s;
}
.video-link:hover { transform: translateY(-1px); background: var(--primary-deep); }
@media (max-width: 560px) {
  .video-card { flex-wrap: wrap; }
  .video-link { width: 100%; text-align: center; }
}

/* 구조도 이미지 */
.arch-img {
  display: block; width: 100%; margin: 14px 0; border-radius: var(--radius);
  border: 1px solid var(--border); box-shadow: var(--shadow); background: #fff;
  cursor: zoom-in; transition: box-shadow .15s, transform .12s;
}
.arch-img:hover { box-shadow: 0 6px 24px rgba(79,110,247,.22); }

/* 영상 폴더 팝업(모달) */
.video-modal {
  position: fixed; inset: 0; z-index: 70; display: none;
  background: rgba(15, 23, 42, .55); backdrop-filter: blur(3px);
  align-items: center; justify-content: center; padding: 20px;
}
.video-modal.open { display: flex; animation: fade .16s ease; }
.vm-card {
  width: 100%; max-width: 460px; background: var(--bg-card); border-radius: var(--radius);
  box-shadow: 0 24px 60px rgba(0,0,0,.35); overflow: hidden; animation: fade .2s ease;
}
.vm-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 18px; font-weight: 800; font-size: 16px; color: var(--ink);
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
}
.vm-close {
  border: none; background: rgba(255,255,255,.7); width: 30px; height: 30px; border-radius: 8px;
  cursor: pointer; font-size: 14px; color: var(--ink-soft); display: grid; place-items: center;
}
.vm-close:hover { background: #fff; color: var(--ink); }
.vm-sub { padding: 12px 18px 4px; font-size: 12.5px; color: var(--ink-faint); }

/* 인라인 플레이어 */
.vm-card.vm-player { max-width: 960px; }
.vm-tabs { display: flex; flex-wrap: wrap; gap: 8px; padding: 14px 18px 6px; }
.vm-tab {
  border: 1px solid var(--border); background: var(--bg); color: var(--ink-soft);
  padding: 8px 16px; border-radius: 999px; font-size: 13.5px; font-weight: 700; cursor: pointer;
  transition: all .12s;
}
.vm-tab:hover { border-color: var(--primary); color: var(--primary-deep); }
.vm-tab.active {
  background: linear-gradient(135deg, var(--primary), var(--primary-deep));
  color: #fff; border-color: transparent; box-shadow: 0 4px 12px rgba(79,110,247,.28);
}
.vm-frame-wrap {
  margin: 10px 18px; border-radius: 12px; overflow: hidden; background: #000;
  height: min(64vh, 540px);
}
.vm-frame { width: 100%; height: 100%; border: 0; display: block; background: #000; }
.vm-foot {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 4px 18px 18px; flex-wrap: wrap;
}
.vm-hint { font-size: 12px; color: var(--ink-faint); }
.vm-ext {
  font-size: 13px; font-weight: 700; color: var(--primary-deep); text-decoration: none;
  white-space: nowrap; border: 1px solid #dfe5ff; background: var(--primary-soft);
  padding: 7px 14px; border-radius: 9px;
}
.vm-ext:hover { background: #fff; }

/* mermaid */
.mermaid {
  position: relative;
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; margin: 20px 0; text-align: center; box-shadow: var(--shadow); overflow-x: auto;
}
.mermaid.zoomable { cursor: zoom-in; transition: border-color .15s, box-shadow .15s; }
.mermaid.zoomable:hover { border-color: var(--primary); box-shadow: 0 4px 20px rgba(79,110,247,.18); }
.mermaid .zoom-hint {
  position: absolute; top: 10px; right: 12px; font-size: 11.5px; color: var(--primary-deep);
  background: var(--primary-soft); border: 1px solid #dfe5ff; padding: 3px 9px; border-radius: 999px;
  opacity: 0; transition: opacity .15s; pointer-events: none;
}
.mermaid.zoomable:hover .zoom-hint { opacity: 1; }

/* 라이트박스(다이어그램 확대 팝업) */
.lightbox {
  position: fixed; inset: 0; z-index: 60; display: none;
  background: rgba(15, 23, 42, .82); backdrop-filter: blur(3px);
}
.lightbox.open { display: block; animation: fade .18s ease; }
.lb-stage {
  position: absolute; inset: 0; overflow: hidden;
  display: flex; align-items: center; justify-content: center;
}
.lb-canvas {
  transform-origin: center center; cursor: grab; will-change: transform;
  display: inline-block; line-height: 0;
}
.lb-canvas.grabbing { cursor: grabbing; }
.lb-canvas svg {
  display: block; background: #fff; border-radius: 12px; padding: 18px;
  box-shadow: 0 20px 60px rgba(0,0,0,.45);
}
.lb-toolbar {
  position: absolute; top: 16px; right: 18px; z-index: 2; display: flex; gap: 8px;
}
.lb-btn {
  width: 40px; height: 40px; border-radius: 10px; border: none; cursor: pointer;
  background: rgba(255,255,255,.92); color: #1f2937; font-size: 18px; font-weight: 700;
  display: grid; place-items: center; box-shadow: 0 4px 12px rgba(0,0,0,.25); transition: transform .12s, background .12s;
}
.lb-btn:hover { transform: translateY(-1px); background: #fff; }
.lb-btn.lb-close { background: #fee2e2; color: #b91c1c; }
.lb-help {
  position: absolute; bottom: 18px; left: 50%; transform: translateX(-50%); z-index: 2;
  color: #e2e8f0; font-size: 12.5px; background: rgba(0,0,0,.35); padding: 6px 14px; border-radius: 999px;
}

/* footer nav between pages */
.page-nav { display: flex; justify-content: space-between; gap: 14px; margin-top: 48px; }
.page-nav a {
  flex: 1; padding: 14px 18px; border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--bg-card); text-decoration: none; color: var(--ink-soft); transition: all .15s;
  box-shadow: var(--shadow);
}
.page-nav a:hover { border-color: var(--primary); color: var(--primary-deep); transform: translateY(-2px); }
.page-nav .dir { font-size: 11px; color: var(--ink-faint); text-transform: uppercase; letter-spacing: .05em; }
.page-nav .name { font-weight: 700; margin-top: 2px; }
.page-nav .next { text-align: right; }
.page-nav .spacer { background: none; border: none; box-shadow: none; pointer-events: none; }

/* ---------- 질문 · 답변 ---------- */
.qna-form {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; margin: 18px 0 8px; box-shadow: var(--shadow);
}
.qna-input, .qna-textarea {
  width: 100%; padding: 10px 12px; margin-bottom: 10px;
  border: 1px solid var(--border); border-radius: 10px; font-size: 14px;
  font-family: inherit; color: var(--ink); background: var(--bg); outline: none;
  transition: border-color .15s, box-shadow .15s; resize: vertical;
}
.qna-input:focus, .qna-textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }
.qna-actions { display: flex; align-items: center; gap: 12px; }
.btn {
  border: none; border-radius: 10px; padding: 10px 20px; font-size: 14px; font-weight: 700;
  cursor: pointer; color: #fff; transition: transform .12s, box-shadow .12s, opacity .12s;
}
.btn:hover { transform: translateY(-1px); }
.btn:disabled { opacity: .6; cursor: default; transform: none; }
.btn-primary { background: linear-gradient(135deg, var(--primary), var(--primary-deep)); box-shadow: 0 6px 16px rgba(79,110,247,.28); }
.btn-accent  { background: linear-gradient(135deg, var(--accent), #0e9488); box-shadow: 0 6px 16px rgba(20,184,166,.25); }
.qna-msg { font-size: 13px; color: var(--ink-faint); }
.qna-msg.err { color: #dc2626; }

.qna-list { display: flex; flex-direction: column; gap: 14px; }
.qna-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
}
.qna-q, .qna-a { display: flex; gap: 12px; padding: 16px 18px; }
.qna-q { background: linear-gradient(135deg, #fafbff, #f4f7ff); }
.qna-a { border-top: 1px dashed var(--border); }
.qna-a.pending { background: #fffdf6; }
.qna-badge {
  flex: 0 0 26px; width: 26px; height: 26px; border-radius: 8px; color: #fff;
  display: grid; place-items: center; font-weight: 800; font-size: 13px;
}
.qna-badge.q { background: var(--primary); }
.qna-badge.a { background: var(--accent); }
.qna-body { flex: 1; min-width: 0; }
.qna-text { color: var(--ink); line-height: 1.65; word-break: break-word; }
.qna-text.pending-text { color: var(--ink-faint); font-style: italic; }
.qna-meta { font-size: 12px; color: var(--ink-faint); margin-top: 6px; }
.qna-answer-edit { margin-top: 12px; }
.qna-answer-edit summary {
  cursor: pointer; font-size: 12.5px; color: var(--primary-deep); font-weight: 600;
  list-style: none; display: inline-block; padding: 4px 0; user-select: none;
}
.qna-answer-edit summary::-webkit-details-marker { display: none; }
.qna-answer-edit summary:hover { text-decoration: underline; }
.qna-answer-edit textarea { margin-top: 8px; }

/* scrollbar */
.sidebar::-webkit-scrollbar, .md pre::-webkit-scrollbar { width: 8px; height: 8px; }
.sidebar::-webkit-scrollbar-thumb, .md pre::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 8px; }

/* backdrop for mobile sidebar */
.backdrop { display: none; position: fixed; inset: 0; background: rgba(15,23,42,.4); z-index: 25; }

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .sidebar {
    position: fixed; left: 0; top: 0; z-index: 30; transform: translateX(-100%);
    transition: transform .25s ease; box-shadow: 0 0 40px rgba(0,0,0,.18);
  }
  .sidebar.open { transform: none; }
  .backdrop.show { display: block; }
  .topbar { display: flex; }
}