:root{--bg: #fff7ed;--card: #ffffff;--text: #3a2f28;--accent: #f97316;--add: #f97316;--sub: #38bdf8;--word: #a78bfa;--correct: #22c55e;--shadow: 0 4px 0 rgba(0, 0, 0, .12)}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}html,body,#root{height:100%;margin:0}body{font-family:-apple-system,BlinkMacSystemFont,Hiragino Maru Gothic ProN,Hiragino Kaku Gothic ProN,Yu Gothic,Meiryo,sans-serif;background:var(--bg);color:var(--text);overflow-x:hidden;-webkit-text-size-adjust:100%}.app{min-height:100%;display:flex;flex-direction:column}.screen{flex:1;display:flex;flex-direction:column;width:100%;max-width:640px;margin:0 auto;padding:max(16px,env(safe-area-inset-top)) 16px max(16px,env(safe-area-inset-bottom))}button{font-family:inherit;cursor:pointer;border:none;-webkit-user-select:none;user-select:none}.home{justify-content:center;align-items:center;gap:12px;text-align:center}.home-title{font-size:clamp(28px,8vw,44px);margin:0;color:var(--accent);letter-spacing:.02em}.home-title-emoji{display:block;font-size:1.4em}.home-subtitle{margin:0 0 16px;font-size:clamp(15px,4vw,20px);color:#8a7a6d}.option-group{display:flex;flex-direction:column;align-items:center;gap:8px;width:100%}.option-group-label{margin:0;width:100%;max-width:360px;font-size:24px;font-weight:700;color:#b8a998;letter-spacing:.08em;text-align:left}.level-list{display:flex;gap:10px;width:100%;max-width:360px}.level-button{flex:1;min-height:48px;border-radius:16px;font-size:clamp(14px,4vw,17px);font-weight:700;color:var(--text);background:#fff;border:2px solid #ddd;transition:transform .08s ease,background-color .08s ease,border-color .08s ease}.level-button-selected{background:#333;border-color:#333;color:#fff;box-shadow:0 0 0 3px #0000001f}.level-button-selected:before{content:"✓ ";font-weight:900}.level-button:active{transform:translateY(1px)}.mode-list{display:flex;flex-direction:column;gap:18px;width:100%;max-width:360px}.mode-button{position:relative;min-height:76px;border-radius:22px;font-size:clamp(24px,7vw,32px);font-weight:700;color:#fff;box-shadow:var(--shadow);transition:transform .08s ease}.mode-button:active{transform:translateY(2px);box-shadow:0 2px #0000001f}.mode-addition{background:var(--add)}.mode-subtraction{background:var(--sub)}.mode-word{background:var(--word)}.quiz{gap:12px}.quiz-topbar{display:flex;align-items:center;gap:12px}.quit-button{flex-shrink:0;background:#fee2e2;color:#b91c1c;border-radius:14px;padding:10px 14px;font-size:16px;font-weight:700;min-height:44px}.quit-button:active{transform:translateY(1px)}.progress{flex:1}.progress-text{font-size:15px;font-weight:700;color:#8a7a6d;margin-bottom:6px;text-align:right}.progress-bar{height:14px;background:#f1e4d6;border-radius:999px;overflow:hidden}.progress-bar-fill{height:100%;background:var(--accent);border-radius:999px;transition:width .3s ease}.quiz-body{flex:3;display:flex;align-items:center;justify-content:center;padding:12px 4px}.quiz-pad-spacer{flex:1}.equation{font-size:clamp(44px,14vw,72px);font-weight:800;letter-spacing:.03em;text-align:center}.equation-q{color:var(--accent)}.word-problem{font-size:clamp(22px,6vw,30px);line-height:1.9;font-weight:600;text-align:left;margin:0;word-break:keep-all;overflow-wrap:break-word}.number-pad{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;padding-top:4px}.number-button{min-width:96px;min-height:96px;aspect-ratio:1 / 1;border-radius:20px;background:var(--card);color:var(--text);font-size:clamp(32px,11vw,48px);font-weight:800;box-shadow:var(--shadow);transition:transform .06s ease}.number-button:active:not(:disabled){transform:translateY(2px);background:#fff3e6}.number-button:disabled{opacity:.5}.feedback{position:fixed;top:0;right:0;bottom:0;left:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;z-index:50;pointer-events:none;animation:pop-in .2s ease}.feedback-correct{background:#dcfce7d1}.feedback-wrong{background:#f1f5f9e6}.feedback-mark{font-size:clamp(96px,30vw,160px);line-height:1;filter:drop-shadow(0 4px 6px rgba(0,0,0,.12));animation:bounce .4s ease}.feedback-message{font-size:clamp(28px,8vw,40px);font-weight:800;color:var(--text)}.feedback-wrong .feedback-message{color:#475569}@keyframes pop-in{0%{opacity:0}to{opacity:1}}@keyframes bounce{0%{transform:scale(.3)}60%{transform:scale(1.15)}to{transform:scale(1)}}.confetti{position:fixed;top:0;right:0;bottom:0;left:0;overflow:hidden;pointer-events:none;z-index:40}.confetti-piece{position:absolute;top:-12%;border-radius:2px;animation-name:confetti-fall;animation-timing-function:linear;animation-iteration-count:1;animation-fill-mode:forwards}@keyframes confetti-fall{0%{transform:translateY(0) rotate(0);opacity:1}to{transform:translateY(115vh) rotate(var(--rot));opacity:1}}.result{justify-content:center;align-items:center;text-align:center;gap:16px}.result-emoji{font-size:clamp(80px,26vw,140px);line-height:1;animation:bounce .5s ease}.result-headline{font-size:clamp(28px,8vw,40px);font-weight:800;color:var(--accent)}.result-score{font-size:clamp(22px,6vw,30px);font-weight:700}.result-score-num{font-size:1.6em;color:var(--correct)}.result-buttons{display:flex;flex-direction:column;gap:16px;width:100%;max-width:320px;margin-top:12px}.big-button{min-height:68px;border-radius:20px;font-size:clamp(20px,6vw,26px);font-weight:800;color:#fff;box-shadow:var(--shadow);transition:transform .08s ease}.big-button:active{transform:translateY(2px)}.primary-button{background:var(--accent)}.secondary-button{background:#94a3b8}@media(prefers-reduced-motion:reduce){.confetti,.feedback-mark,.result-emoji,.feedback{animation:none!important}}