:root {
  --yellow: #FFD93D;
  --coral: #FF6B6B;
  --mint: #6BCB77;
  --blue: #4D96FF;
  --purple: #C77DFF;
  --orange: #FF9A3C;
  --bg: #fef9f0;
  --card: #ffffff;
  --text: #2d2d2d;
  --sub: #888;
  --border: #e0d6c8;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'Noto Sans KR', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.ad-slot {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 90px;
  margin: 16px auto;
  max-width: 640px;
  border: 1px dashed #d8cdb9;
  border-radius: 12px;
  background: #fffdf8;
}
.ad-label {
  font-size: 12px;
  letter-spacing: 0.05em;
  color: #bbb;
}

/* 도구 간 이동 네비게이션 */
.tool-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  max-width: 640px;
  margin: 16px auto 0;
  padding: 0 16px;
}
.tool-nav-item {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 8px 14px;
  border-radius: 999px;
  background: #fff;
  border: 1.5px solid #ccc;
  color: #888;
  font-size: 0.85rem;
  font-weight: 700;
  text-decoration: none;
  transition: all 0.15s;
}
.tool-nav-item:hover {
  border-color: #666;
  color: #444;
}
.tool-nav-item.active {
  border-color: #222;
  color: #222;
}

.tools_header {
  background: linear-gradient(135deg, #FFD93D 0%, #FF9A3C 100%);
  padding: 36px 20px 28px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.tools_header::before {
  content: '';
  position: absolute;
  top: -40px; right: -40px;
  width: 180px; height: 180px;
  background: rgba(255,255,255,0.15);
  border-radius: 50%;
}
.tools_header h1 {
  font-family: 'Gaegu', cursive;
  font-size: 2.4rem;
  color: #fff;
  text-shadow: 2px 3px 0 rgba(0,0,0,0.12);
  position: relative; z-index: 1;
}
.tools_header p {
  color: rgba(255,255,255,0.92);
  font-size: 0.95rem;
  margin-top: 6px;
  position: relative; z-index: 1;
}

.game-main {
  max-width: 640px;
  margin: 0 auto;
  padding: 0 16px;
}

.panel {
  background: var(--card);
  border-radius: 24px;
  padding: 28px 22px;
  box-shadow: 0 4px 24px rgba(0,0,0,0.07);
  border: 2px solid var(--border);
  text-align: center;
}

.panel h2 {
  font-family: 'Gaegu', cursive;
  font-size: 1.5rem;
  margin-bottom: 20px;
  color: #444;
}

/* 난이도 선택 */
.level-grid {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.level-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 56px;
  padding: 14px 18px;
  border: 2px solid var(--border);
  border-radius: 16px;
  background: #fafafa;
  font-family: 'Gaegu', cursive;
  font-size: 1.3rem;
  font-weight: 700;
  color: #444;
  cursor: pointer;
  transition: all 0.2s;
  text-align: center;
  width: 100%;
}
.level-btn:hover {
  border-color: var(--orange);
  background: #fff8ec;
  transform: translateY(-2px);
}

/* 게임 진행 화면 */
.level-indicator {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 12px;
  font-size: 0.85rem;
  color: var(--sub);
  font-weight: 700;
}
.btn-change {
  background: #f0f0f0;
  border: 1px solid #e0e0e0;
  color: #888;
  border-radius: 999px;
  padding: 3px 12px;
  font-size: 0.75rem;
  font-family: 'Noto Sans KR', sans-serif;
  cursor: pointer;
}
.btn-change:hover {
  background: #e5e5e5;
}

.game-status {
  display: flex;
  justify-content: space-between;
  font-size: 0.9rem;
  color: var(--sub);
  font-weight: 700;
  margin-bottom: 20px;
}

.question-prompt {
  font-family: 'Gaegu', cursive;
  font-size: 1.15rem;
  color: #444;
  margin-bottom: 16px;
}
.question-prompt.prompt-correct {
  color: #e06c00;
  font-weight: 700;
}
.question-prompt.prompt-wrong {
  color: var(--coral);
  font-weight: 700;
}

/* 분수 비교 문제 (숫자만 표시) */
.compare-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin-bottom: 20px;
}
.frac-display {
  flex: 0 0 auto;
}

.symbol-slot {
  flex: 0 0 auto;
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: #fafafa;
  border: 2.5px dashed var(--border);
  font-family: 'Gaegu', cursive;
  font-size: 1.8rem;
  font-weight: 700;
  color: #bbb;
}
.symbol-slot.symbol-correct {
  border-style: solid;
  border-color: transparent;
  background: linear-gradient(135deg, #FFD93D, #FF9A3C);
  color: #fff;
}
.symbol-slot.symbol-reveal {
  border-style: solid;
  border-color: var(--coral);
  background: #ffe5e5;
  color: var(--coral);
}

.symbol-choices {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}
.symbol-btn {
  padding: 18px 10px;
  border: 2.5px solid var(--border);
  border-radius: 16px;
  background: #fafafa;
  font-family: 'Gaegu', cursive;
  font-size: 2rem;
  font-weight: 700;
  color: #444;
  cursor: pointer;
  transition: all 0.15s;
}
.symbol-btn:hover:not(:disabled) {
  border-color: var(--orange);
  transform: translateY(-2px);
}
.symbol-btn:disabled {
  cursor: default;
}
.symbol-btn.correct {
  background: linear-gradient(135deg, #FFD93D, #FF9A3C);
  border-color: transparent;
  color: #fff;
}
.symbol-btn.wrong {
  background: #ffe5e5;
  border-color: var(--coral);
  color: var(--coral);
}

/* 세로 분수 — 공용 컴포넌트 */
.kr-frac {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  font-family: 'Gaegu', cursive;
  font-weight: 700;
  line-height: 1;
  gap: 1px;
}
.kr-frac .kf-num  { font-size: 1.05rem; }
.kr-frac .kf-line { width: 22px; height: 2.5px; background: currentColor; border-radius: 2px; margin: 1px 0; }
.kr-frac .kf-den  { font-size: 1.05rem; }
.frac-display .kr-frac .kf-num,
.frac-display .kr-frac .kf-den { font-size: 2.1rem; color: #444; }
.frac-display .kr-frac .kf-line { width: 34px; height: 4px; }

/* 정답 설명용 파이 그림 */
.explain-pies {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  margin-bottom: 16px;
}
.explain-pies .pie-wrap {
  width: 72px;
  height: 72px;
}
.vs-label-small {
  font-family: 'Gaegu', cursive;
  font-size: 0.9rem;
  color: #bbb;
  font-weight: 700;
}

/* 정답 설명 */
.explain {
  border-top: 2px dashed var(--border);
  padding-top: 20px;
  margin-top: 10px;
}
.explain-array {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 12px;
}
.comp-row {
  display: flex;
  align-items: center;
  gap: 10px;
}
.comp-label {
  min-width: 40px;
  display: flex;
  justify-content: flex-end;
  align-items: center;
}
.comp-track {
  flex: 1;
  height: 26px;
  background: #f0f0f0;
  border-radius: 8px;
  overflow: hidden;
  position: relative;
}
.comp-fill {
  height: 100%;
  border-radius: 8px;
  transition: width 0.6s cubic-bezier(0.34, 1.1, 0.64, 1);
  min-width: 4px;
}
.comp-pct {
  min-width: 44px;
  font-size: 0.82rem;
  color: #888;
  font-weight: 700;
}

.explain-text {
  font-family: 'Gaegu', cursive;
  font-size: 1.15rem;
  color: #444;
  margin-bottom: 18px;
  line-height: 1.6;
}

.btn-next {
  background: linear-gradient(135deg, #FF9A3C, #FF6B6B);
  color: #fff;
  border: none;
  border-radius: 14px;
  padding: 14px 24px;
  font-family: 'Gaegu', cursive;
  font-size: 1.2rem;
  cursor: pointer;
  box-shadow: 0 4px 14px rgba(255,107,107,0.3);
}
.btn-next:hover { transform: translateY(-2px); }

/* 결과 화면 */
.result-score {
  font-family: 'Gaegu', cursive;
  font-size: 3rem;
  font-weight: 700;
  color: #e06c00;
  margin: 10px 0;
}
.result-message {
  font-size: 1rem;
  color: #555;
  margin-bottom: 24px;
}
.actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: center;
}
.btn-visualize {
  background: linear-gradient(135deg, #FF9A3C, #FF6B6B);
  color: #fff;
  border: none;
  border-radius: 14px;
  padding: 14px 20px;
  font-family: 'Gaegu', cursive;
  font-size: 1.1rem;
  cursor: pointer;
  box-shadow: 0 4px 14px rgba(255,107,107,0.3);
}
.btn-reset {
  background: #f0f0f0;
  border: 2px solid #e0e0e0;
  color: #888;
  border-radius: 14px;
  padding: 14px 18px;
  font-size: 0.95rem;
  cursor: pointer;
  font-family: 'Noto Sans KR', sans-serif;
}
.btn-next-level {
  background: linear-gradient(135deg, #C77DFF, #4D96FF);
  color: #fff;
  border: none;
  border-radius: 14px;
  padding: 14px 20px;
  font-family: 'Gaegu', cursive;
  font-size: 1.1rem;
  cursor: pointer;
  box-shadow: 0 4px 14px rgba(199,125,255,0.3);
}
.btn-next-level:hover { transform: translateY(-2px); }

.tools_footer {
  text-align: center;
  padding: 40px 20px 20px;
  font-size: 0.8rem;
  color: #bbb;
}

@media (max-width: 420px) {
  .tools_header h1 { font-size: 2rem; }
  .frac-display .kr-frac .kf-num,
  .frac-display .kr-frac .kf-den { font-size: 1.7rem; }
  .symbol-btn { font-size: 1.6rem; padding: 14px 8px; }
  .explain-pies .pie-wrap { width: 60px; height: 60px; }
}