:root {
  --bg: #17181a; --panel: #212226; --panel2: #2a2c31; --border: #3a3d44;
  --fg: #ececee; --fg2: #c9ccd3; --dim: #a1a5ad; --accent: #4f8cff; --accent-fg: #fff; --sel: #f0b43c;
  --gutter: 16px;
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--fg);
  font: 15px/1.55 system-ui, -apple-system, "Segoe UI", "Noto Sans KR", sans-serif; }
[hidden] { display: none !important; }
header { position: sticky; top: 0; z-index: 5; display: flex; align-items: center; gap: 12px;
  justify-content: space-between; padding: 10px var(--gutter); background: var(--panel);
  border-bottom: 1px solid var(--border); }
header h1 { font-size: 15px; margin: 0; font-weight: 600; }
.hdr-right { display: flex; align-items: center; gap: 12px; }
#progress { color: var(--dim); font-variant-numeric: tabular-nums; }
main { padding: 16px var(--gutter) 48px; max-width: 1800px; margin: 0 auto; }
.card { background: var(--panel); border: 1px solid var(--border); border-radius: 10px; padding: 20px 24px; }
.narrow { max-width: 760px; margin: 24px auto; }
h2 { font-size: 20px; margin: 0 0 10px; }
.small { font-size: 13px; }
.dim { color: var(--dim); }
button { font: inherit; cursor: pointer; border-radius: 8px; padding: 8px 16px; border: 1px solid var(--border); }
button:disabled { opacity: .45; cursor: not-allowed; }
.primary { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); font-weight: 600; }
.ghost { background: var(--panel2); color: var(--fg); }
.row-end { display: flex; justify-content: flex-end; align-items: center; gap: 14px; margin-top: 14px; }
/* 맨 아래 줄: 왼쪽 '이전', 오른쪽 '다음' */
.nav { display: flex; align-items: center; gap: 14px; margin-top: 14px; }
.nav #next-hint { margin-left: auto; }
.consent { display: flex; gap: 8px; align-items: flex-start; margin: 12px 0; }
.code { font-size: 18px; } .code b { letter-spacing: .06em; color: var(--sel); }

.context { display: grid; grid-template-columns: 1fr; gap: 8px; margin-bottom: 12px; }
.lbl { font-size: 12px; color: var(--dim); text-transform: uppercase; letter-spacing: .05em; margin-right: 8px; }
.prompt { display: flex; align-items: baseline; background: var(--panel); border: 1px solid var(--border);
  border-radius: 8px; padding: 8px 12px; }
.prompt .lbl { flex: none; }
.ptext { min-width: 0; }
#prompt-ko { margin-top: 2px; color: var(--fg2); }
/* 레퍼런스 사진: 처음부터 크게 — 5칸 격자로 한 장이 본문 폭의 1/5 을 그대로 채운다
   (1920px 화면에서 약 330px, 1440px 노트북에서 약 270px). 누르면 원본 크기로도 볼 수 있다. */
.refs-block { display: grid; gap: 6px; }
.refs-head { display: flex; align-items: baseline; gap: 10px; }
#refs { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 10px; }
#refs img { width: 100%; aspect-ratio: 1 / 1; object-fit: contain; background: #000;
  border: 1px solid var(--border); border-radius: 8px; cursor: zoom-in; }
#lightbox { position: fixed; inset: 0; z-index: 50; background: rgba(0, 0, 0, .88); display: flex;
  align-items: center; justify-content: center; cursor: zoom-out; padding: 2vh 2vw; }
#lightbox img { max-width: 96vw; max-height: 94vh; object-fit: contain; border-radius: 6px; }

/* 영상 아래 한 줄: 재생 · 가로 탐색 막대 · 시각 · 처음부터 */
.scrub { display: grid; grid-template-columns: auto 1fr auto auto; gap: 6px 12px; align-items: center;
  position: sticky; bottom: 0; z-index: 4; margin: 10px 0 14px; padding: 10px 14px calc(8px + env(safe-area-inset-bottom, 0px));
  background: var(--panel); border: 1px solid var(--border); border-radius: 10px;
  box-shadow: 0 -6px 18px rgba(0, 0, 0, .35); }
#seek { width: 100%; height: 28px; accent-color: var(--accent); cursor: pointer; }
.scrub .watch { grid-column: 1 / -1; font-size: 13px; }
.scrub .watch:empty { display: none; }

/* 영상 격자: 한 줄에 --cols 개, 남는 줄은 가운데로 (5개면 3 + 2) */
.grid { --cols: 3; display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.grid figure { flex: 0 0 calc((100% - (var(--cols) - 1) * 12px) / var(--cols)); min-width: 0; }
figure { margin: 0; background: #000; border: 1px solid var(--border); border-radius: 8px; overflow: hidden; }
figcaption { padding: 2px 12px; font-size: 18px; font-weight: 800; background: var(--panel);
  border-bottom: 1px solid var(--border); }
video { display: block; width: 100%; aspect-ratio: 832 / 480; object-fit: contain; background: #000; }
#clock { font-variant-numeric: tabular-nums; }

.q { display: grid; grid-template-columns: 1fr auto; gap: 12px; align-items: center; padding: 10px 12px;
  background: var(--panel); border: 1px solid var(--border); border-radius: 8px; margin-bottom: 8px; }
.q .opts { display: flex; gap: 8px; }
.q .opts { flex-wrap: wrap; }
.q .opts button { min-width: 52px; font-weight: 700; background: var(--panel2); color: var(--fg); }
.q .opts button.on { background: var(--sel); color: #111; border-color: var(--sel); font-weight: 700; }

@media (max-width: 1100px) {
  .grid figure { flex-basis: calc((100% - 12px) / 2); }
}
@media (max-width: 900px) {
  .q { grid-template-columns: 1fr; }
  #refs { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .scrub { grid-template-columns: auto 1fr; }
  .scrub #clock, .scrub #restart { grid-column: auto; }
}
@media (max-width: 640px) {
  .grid figure { flex-basis: 100%; }
}