/* 사칙연산 암산 모듈 전용 스타일 — 챌린지/유형/스테이지 선택 화면, 플레이 화면의 문제 카드.
   공통 껍데기(화면 전환·카드·타이머·결과·랭킹등록)는 shared/css/game-shell.css,
   버튼·nav·푸터·모달·랭킹행은 shared/css/{base,nav,footer,modal,rank}.css 참고(허브와 공용).
   2026-07-23 완전 무료 전환: 3·4자리/혼합 결제 게이트(is-locked, stage-card__lock, paywall-modal) 전부 제거 —
   구모델(결제 게이트)의 흔적은 04_storyboard/story_board 아래 원본 addition_game.html에 이력으로만 남아있음. */

.stage {
  position: relative;
  min-height: calc(100vh - 60px);
  /* flex-direction 기본값(row)이면 월간대회 배너(.cup-round-banner)가 .screen 카드와
     나란히 가로로 놓여 가운데 정렬 그룹째로 왼쪽에 밀려 보인다(2026-08-06) — column으로
     세로 스택. 평소(배너 없이 .screen 하나만 보일 때)는 항목이 1개뿐이라 결과 동일. */
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  padding: 32px 20px; overflow: hidden;
  background:
    radial-gradient(circle at 16% 22%, rgba(0,85,157,.07), transparent 42%),
    radial-gradient(circle at 84% 78%, rgba(255,106,61,.08), transparent 45%),
    radial-gradient(rgba(0,85,157,.08) 1px, transparent 1px) 0 0 / 28px 28px,
    var(--bg);
}
.deco { position: absolute; inset: 0; pointer-events: none; z-index: 0; }
.deco-symbol { position: absolute; font-weight: 800; color: var(--primary); opacity: .06; line-height: 1; user-select: none; }
.deco-symbol--1 { top: 8%; left: 8%; font-size: 140px; transform: rotate(-12deg); }
.deco-symbol--2 { top: 62%; left: 6%; font-size: 100px; transform: rotate(8deg); color: var(--game); opacity: .09; }
.deco-symbol--3 { top: 14%; right: 8%; font-size: 110px; transform: rotate(10deg); }
.deco-symbol--4 { bottom: 10%; right: 10%; font-size: 130px; transform: rotate(-6deg); color: var(--game); opacity: .08; }
.deco-symbol--5 { bottom: 6%; left: 42%; font-size: 90px; transform: rotate(-16deg); }
@media (max-width: 640px) { .deco-symbol { display: none; } }

.benefit-strip { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px; margin-top: -12px; margin-bottom: 24px; }
.benefit-strip__item {
  display: inline-flex; align-items: center; gap: 5px; font-size: 11px; font-weight: 700;
  color: var(--primary); background: var(--primary-pale); border-radius: 999px; padding: 6px 10px;
}
.benefit-strip__item .icon { width: 14px; height: 14px; flex-shrink: 0; }

/* 챌린지(연산 종류) 선택 */
.op-select { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 8px; }
.op-card {
  position: relative; display: flex; flex-direction: column; align-items: center; text-align: center; gap: 4px;
  border: 1px solid var(--line); background: var(--surface); border-radius: var(--radius-md);
  padding: 18px 12px; cursor: pointer;
  transition: border-color .15s ease, box-shadow .15s ease, transform .15s ease;
}
.op-card:hover { border-color: var(--primary); box-shadow: 0 6px 16px rgba(0,85,157,.12); transform: translateY(-1px); }
.op-card__tag { font-size: 10px; font-weight: 700; letter-spacing: .06em; color: var(--game); }
.op-card__title { font-size: 16px; font-weight: 800; color: var(--primary-dark); }
.op-card__desc { font-size: 11px; color: var(--text-mute); line-height: 1.35; margin-top: 2px; min-height: 2.7em; }
.op-card__soon { display: none; margin-top: auto; font-size: 11px; font-weight: 700; color: var(--text-mute); background: var(--bg); border-radius: 999px; padding: 2px 8px; margin-top: 2px; }
.op-card.is-soon { opacity: .62; }
.op-card.is-soon .op-card__soon { display: inline-block; }
.op-card--mixed { grid-column: 1 / -1; }

/* 유형 선택 */
.type-select { display: flex; flex-direction: column; gap: 12px; margin-bottom: 8px; }
.type-card {
  display: flex; flex-direction: column; align-items: flex-start; gap: 4px; text-align: left;
  border: 1px solid var(--line); background: var(--surface); border-radius: var(--radius-md);
  padding: 18px 20px; cursor: pointer;
  transition: border-color .15s ease, box-shadow .15s ease, transform .15s ease;
}
.type-card:hover { border-color: var(--primary); box-shadow: 0 6px 16px rgba(0,85,157,.12); transform: translateY(-1px); }
.type-card__badge { display: inline-block; font-size: 11px; font-weight: 700; color: var(--primary); background: var(--primary-pale); border-radius: 999px; padding: 3px 10px; margin-bottom: 2px; }
.type-card[data-type="2"] .type-card__badge { color: var(--game); background: var(--game-pale); }
.type-card__title { font-size: 16px; font-weight: 800; color: var(--primary-dark); }
.type-card__desc { font-size: 13px; color: var(--text-mute); line-height: 1.5; }
.type-card__soon { display: none; font-size: 11px; font-weight: 700; color: var(--text-mute); background: var(--bg); border-radius: 999px; padding: 2px 8px; margin-top: 2px; }
.type-card.is-soon { opacity: .62; }
.type-card.is-soon .type-card__soon { display: inline-block; }

.brand-slogan { margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--line); text-align: center; }
.brand-slogan__title { font-size: 13px; font-weight: 800; color: var(--primary); letter-spacing: .02em; margin-bottom: 6px; }
.brand-slogan__body { font-size: 12px; color: var(--text-mute); line-height: 1.6; }

/* 스테이지 선택 — 전부 무료라 잠금 표시 없음 */
.stage-select { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 16px; }
.stage-card {
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  border: 1px solid var(--line); background: var(--surface); border-radius: var(--radius-md);
  padding: 18px 12px; cursor: pointer;
  transition: border-color .15s ease, box-shadow .15s ease, transform .15s ease;
}
.stage-card:hover { border-color: var(--primary); box-shadow: 0 6px 16px rgba(0,85,157,.12); transform: translateY(-1px); }
.stage-card__tag { font-size: 10px; font-weight: 700; letter-spacing: .06em; color: var(--game); }
.stage-card__digits { font-size: 20px; font-weight: 800; color: var(--primary-dark); }
.stage-card__points { font-size: 12px; color: var(--text-mute); }
.stage-card--mixed { grid-column: 1 / -1; border-color: var(--game); background: var(--game-pale); }
.stage-card--mixed .stage-card__digits { color: var(--game); }
.stage-card--mixed .stage-card__points { color: #C2410C; max-width: 320px; line-height: 1.4; }

.stage-card.is-selected { border-color: var(--primary); background: var(--primary-pale); box-shadow: 0 6px 16px rgba(0,85,157,.18); }
.stage-card.is-selected .stage-card__digits { color: var(--primary); }
.stage-card--mixed.is-selected { border-color: var(--game); background: #FCEFC7; }

.stage-select__footer { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.stage-select__count { flex-shrink: 0; font-size: 12px; font-weight: 700; color: var(--text-mute); white-space: nowrap; }
.stage-select__footer .btn { flex: 1; padding: 12px 16px; }
.stage-select__hint { font-size: 12px; color: var(--text-mute); }

.screen#screen-play.is-active { flex-direction: column; align-items: center; }
.play-title-sticky, .play-hud-sticky { display: flex; flex-direction: column; align-items: center; width: 100%; }
@media (max-width: 640px) {
  /* ⚠️ top 오프셋(50px)은 .play-title-sticky의 대략적인 렌더 높이를 하드코딩한 값 — 타이틀 pill 크기가 바뀌면 같이 조정 필요 */
  .play-title-sticky { position: sticky; top: 0; z-index: 21; padding-top: 8px; }
  .play-hud-sticky { position: sticky; top: 50px; z-index: 20; }
}
.play-challenge {
  display: inline-flex; align-items: center; gap: 7px; margin: 0 auto 24px; padding: 7px 18px; border-radius: 999px;
  background: linear-gradient(135deg, var(--primary-pale), var(--game-pale)); border: 1px solid var(--line);
  box-shadow: 0 3px 10px rgba(0,85,157,.1);
}
.play-challenge__icon { width: 17px; height: 17px; color: var(--game); }
.play-challenge__text { font-size: 16px; font-weight: 800; color: var(--primary-dark); letter-spacing: -.01em; }

.stage-stepper { display: flex; gap: 6px; width: 100%; max-width: 420px; margin-bottom: 16px; }
.stepper-step {
  flex: 1; display: flex; flex-direction: column; align-items: center; gap: 2px; text-align: center;
  font-size: 12px; font-weight: 700; color: var(--text-mute); background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius-md); padding: 6px 4px;
  transition: background .2s ease, color .2s ease, border-color .2s ease, transform .2s ease;
}
.stepper-step em { font-style: normal; font-size: 9px; font-weight: 700; letter-spacing: .06em; opacity: .7; }
.stepper-step.is-done { border-color: var(--correct); color: var(--correct); background: var(--correct-bg); }
.stepper-step.is-active { background: var(--primary); border-color: var(--primary); color: var(--surface); transform: scale(1.05); }
.stepper-step[data-level="5"].is-active { background: var(--game); border-color: var(--game); }

.card--play { padding: 48px 32px; }
.problem { font-size: 40px; font-weight: 800; color: var(--text); margin-bottom: 28px; letter-spacing: -.02em; transition: color .15s ease; }
.problem.is-correct { color: var(--correct); }
.problem.is-wrong { color: var(--wrong); }

.answer-form { display: flex; gap: 10px; }
.answer-form .btn { flex-shrink: 0; }
.answer-input {
  flex: 1; min-width: 0; font-size: 20px; font-weight: 700; text-align: center; padding: 14px;
  border: 2px solid var(--line); border-radius: var(--radius-md); color: var(--text);
  transition: border-color .15s ease, background .15s ease;
}
.answer-input:focus { outline: none; border-color: var(--primary); }
.answer-input.is-correct { border-color: var(--correct); background: var(--correct-bg); }
.answer-input.is-wrong { border-color: var(--wrong); background: var(--wrong-bg); }
.answer-form.is-hidden { display: none; }

.judge-actions { display: none; gap: 12px; }
.judge-actions.is-active { display: flex; }
.btn--judge { flex: 1; font-size: 16px; padding: 16px; }
.btn--judge-true { background: var(--correct); color: var(--surface); }
.btn--judge-true:hover { background: #128A3A; }
.btn--judge-false { background: var(--wrong); color: var(--surface); }
.btn--judge-false:hover { background: #B91C1C; }

@media (max-width: 480px) { .problem { font-size: 32px; } }