/* ============================================================
   색감 테스트 전용 스타일
   - 색을 판단하는 게임이라 배경은 색 판단을 방해하지 않는 중립 톤.
   - 격자는 틈 없이 붙여(seamless) 오직 색으로만 다른 칸을 찾게 한다.
   - 타일 색은 자체 생성(테마 무관) → 라이트/다크에서 난이도가 같다.
   ============================================================ */

/* ---- 도입부 ---- */
.tool-intro { padding: clamp(30px, 5vw, 56px) 0 clamp(14px, 3vw, 26px); }
.tool-intro h1 { margin: 0 0 var(--space-4); }
.tool-intro .lead {
  font-size: 1.08rem;
  line-height: 1.75;
  color: var(--color-text-sub);
  max-width: 52ch;
  margin: 0;
}
.tool-intro .lead strong { color: var(--color-text); }
.tool-intro .lead-note {
  margin: var(--space-3) 0 0;
  font-size: .88rem;
  color: var(--color-text-sub);
}

/* ---- 게임판 영역 ---- */
.ch-stage { max-width: 520px; margin: 0 auto; }

/* HUD: 레벨 · 색 차이 막대 · 최고 기록 */
.ch-hud {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-bottom: var(--space-3);
}
.ch-stat { font-variant-numeric: tabular-nums; color: var(--color-text-sub); font-size: .95rem; }
.ch-stat b { display: block; font-size: 1.5rem; color: var(--color-text); line-height: 1.1; font-variant-numeric: tabular-nums; }
.ch-delta { flex: 1; min-width: 0; }
.ch-delta-head {
  display: flex; justify-content: space-between; align-items: baseline;
  font-size: .8rem; color: var(--color-text-sub); margin-bottom: 4px;
}
.ch-delta-head b { color: var(--color-text); font-variant-numeric: tabular-nums; }
.ch-meter { height: 8px; border-radius: 999px; background: var(--color-border); overflow: hidden; }
.ch-meter-fill {
  height: 100%;
  background: var(--color-primary);
  border-radius: 999px;
  transition: width .2s ease;
}

/* 라운드 타이머 막대 */
.ch-timewrap {
  height: 8px;
  border-radius: 999px;
  background: var(--color-border);
  overflow: hidden;
  margin-bottom: var(--space-3);
}
.ch-timebar {
  height: 100%;
  width: 100%;
  transform-origin: left center;
  background: var(--color-text-sub);
  border-radius: 999px;
}
.ch-timebar.is-low { background: var(--color-primary); }

/* 격자: 정사각, 틈 없이 붙여 색으로만 구분 */
.ch-board-wrap { position: relative; }
.ch-board {
  --n: 2;
  display: grid;
  grid-template-columns: repeat(var(--n), 1fr);
  aspect-ratio: 1 / 1;
  width: 100%;
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  background: #808080; /* 로딩 전 중립 회색(테마 무관) */
  touch-action: manipulation;
}
.ch-tile {
  border: 0;
  padding: 0;
  margin: 0;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  -webkit-user-select: none;
  user-select: none;
  width: 100%;
  height: 100%;
  outline: none;
}
.ch-tile:focus-visible { box-shadow: inset 0 0 0 3px rgba(255,255,255,.85), inset 0 0 0 6px rgba(0,0,0,.5); }
.ch-tile.is-correct { box-shadow: inset 0 0 0 4px rgba(255,255,255,.9), inset 0 0 0 8px rgba(0,0,0,.5); }
.ch-tile.is-reveal {
  box-shadow: inset 0 0 0 4px rgba(255,255,255,.95), inset 0 0 0 9px rgba(0,0,0,.6);
  animation: ch-pulse 1s ease infinite;
}
@keyframes ch-pulse { 50% { box-shadow: inset 0 0 0 6px rgba(255,255,255,1), inset 0 0 0 11px rgba(0,0,0,.7); } }

/* ---- 오버레이(시작 / 종료) ---- */
.ch-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: var(--space-2);
  padding: var(--space-5);
  border-radius: 14px;
  background: color-mix(in srgb, var(--color-bg) 84%, transparent);
  -webkit-backdrop-filter: blur(3px);
          backdrop-filter: blur(3px);
}
@supports not (background: color-mix(in srgb, red 50%, transparent)) {
  .ch-overlay { background: rgba(243, 240, 232, .9); }
  :root[data-theme="dark"] .ch-overlay { background: rgba(23, 19, 14, .9); }
}
.ch-over-eyebrow { margin: 0; font-size: 1rem; color: var(--color-text-sub); }
.ch-over-title { margin: 0; font-family: var(--font-serif); font-weight: 700; font-size: 1.6rem; }
.ch-over-score { margin: 0; font-family: var(--font-serif); line-height: 1.05; }
.ch-over-score b { font-size: 3.4rem; color: var(--color-primary); }
.ch-over-score span { font-size: 1.3rem; color: var(--color-text-sub); margin-left: 4px; }
.ch-over-comment { margin: var(--space-1) 0 0; font-size: 1.05rem; font-weight: 700; max-width: 30ch; }
.ch-over-best { margin: 0; font-size: .95rem; color: var(--color-text-sub); font-variant-numeric: tabular-nums; }
.ch-over-note { margin: var(--space-2) 0 0; font-size: .82rem; color: var(--color-text-sub); max-width: 34ch; }

.ch-btn-big {
  font: inherit;
  font-size: 1.25rem;
  font-weight: 700;
  cursor: pointer;
  touch-action: manipulation;
  margin-top: var(--space-3);
  padding: 15px 40px;
  border-radius: 999px;
  border: 0;
  background: var(--color-primary);
  color: #fff;
  box-shadow: var(--shadow);
}
.ch-btn-big:hover { filter: brightness(1.06); }
.ch-btn-big:active { transform: scale(.97); }

/* ---- 의료 선긋기 안내 ---- */
.ch-disclaimer {
  max-width: 520px;
  margin: var(--space-4) auto 0;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  font-size: .88rem;
  color: var(--color-text-sub);
}

/* ---- 본문 ---- */
.prose { max-width: 720px; margin: clamp(40px, 6vw, 64px) auto 0; }
.prose h2 { margin: 0 0 var(--space-3); }
.prose p { margin: 0 0 var(--space-3); color: var(--color-text); }
.prose ul { margin: 0; padding-left: 1.2em; }
.prose li { margin-bottom: var(--space-2); }
.prose li strong { color: var(--color-text); }

@media (prefers-reduced-motion: reduce) {
  .ch-meter-fill, .ch-btn-big { transition: none; }
  .ch-tile.is-reveal { animation: none; }
}