.subtraction-game-container{background:#fafafa;flex-direction:column;min-height:100vh;padding:1.5rem;display:flex;overflow-y:auto}.game-header{justify-content:space-between;align-items:center;gap:1rem;max-width:1200px;margin:0 auto 1.5rem;display:flex}.back-button,.stats-toggle{color:#3b82f6;cursor:pointer;background:#fff;border:3px solid #3b82f6;border-radius:12px;padding:.75rem 1.5rem;font-size:1rem;font-weight:700;text-decoration:none;transition:all .3s;display:inline-block;transform:translateY(-2px);box-shadow:0 4px #3b82f6,0 6px 12px #3b82f633}.back-button:hover,.stats-toggle:hover{transform:translateY(-4px);box-shadow:0 6px #3b82f6,0 8px 16px #3b82f64d}.game-title{color:#1a1a1a;text-align:center;flex:1;margin:0;font-size:clamp(1.5rem,4vw,2.5rem);font-weight:900}.score-bar{background:#fff;border:4px solid #3b82f6;border-radius:16px;justify-content:space-around;gap:1rem;max-width:1200px;margin:0 auto 1.5rem;padding:1rem 1.5rem;display:flex;transform:translateY(-3px);box-shadow:0 6px #3b82f6,0 10px 20px #3b82f626}.score-item{flex-direction:column;align-items:center;gap:.25rem;display:flex}.score-label{color:#666;font-size:.85rem;font-weight:600}.score-value{color:#1a1a1a;font-size:1.5rem;font-weight:900}.score-value.correct{color:#10b981}.score-value.wrong{color:#ef4444}.stats-panel{background:#fff;border:4px solid #3b82f6;border-radius:20px;max-width:800px;margin:0 auto;padding:2.5rem;transform:translateY(-5px);box-shadow:0 10px #3b82f6,0 15px 30px #3b82f626}.stats-panel h2{text-align:center;color:#1a1a1a;margin:0 0 2rem;font-size:2rem;font-weight:900}.stats-grid{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:1.5rem;margin-bottom:2rem;display:grid}.stat-card{text-align:center;background:#fff;border:3px solid #3b82f6;border-radius:12px;padding:1.5rem;transform:translateY(-3px);box-shadow:0 6px #3b82f6,0 10px 20px #3b82f61f}.stat-value{color:#3b82f6;margin-bottom:.5rem;font-size:2.5rem;font-weight:900}.stat-label{color:#666;font-size:.9rem;font-weight:600}.reset-button{color:#ef4444;cursor:pointer;background:#fff;border:3px solid #ef4444;border-radius:12px;width:100%;padding:1rem;font-size:1.1rem;font-weight:800;transition:all .3s;transform:translateY(-2px);box-shadow:0 4px #ef4444,0 6px 12px #ef444433}.reset-button:hover{transform:translateY(-4px);box-shadow:0 6px #ef4444,0 8px 16px #ef44444d}.start-screen{text-align:center;background:#fff;border:4px solid #3b82f6;border-radius:20px;max-width:600px;margin:2rem auto;padding:3rem 2rem;transform:translateY(-5px);box-shadow:0 10px #3b82f6,0 15px 30px #3b82f626}.start-screen h2{color:#1a1a1a;margin:0 0 1rem;font-size:2rem;font-weight:900}.start-screen p{color:#666;margin-bottom:1.5rem;font-size:1.1rem}.instructions{margin:0 0 2rem;padding:0;list-style:none}.instructions li{color:#1a1a1a;background:#f8fafc;border-radius:8px;margin-bottom:.5rem;padding:.75rem 1rem;font-size:1.1rem;font-weight:600}.start-button{color:#3b82f6;cursor:pointer;background:#fff;border:3px solid #3b82f6;border-radius:12px;margin-bottom:1rem;padding:1rem 3rem;font-size:1.3rem;font-weight:800;transition:all .3s;transform:translateY(-3px);box-shadow:0 6px #3b82f6,0 10px 20px #3b82f633}.start-button:hover{transform:translateY(-6px);box-shadow:0 9px #3b82f6,0 13px 26px #3b82f64d}.keyboard-hint{color:#999;margin:0;font-size:.9rem}.countdown-screen{text-align:center;padding:4rem 2rem}.countdown-number{color:#1a1a1a;font-size:8rem;font-weight:900;animation:1s ease-in-out pulse}.countdown-screen p{color:#666;margin:1rem 0 0;font-size:2rem;font-weight:700}@keyframes pulse{0%,to{opacity:1;transform:scale(1)}50%{opacity:.8;transform:scale(1.1)}}.question-area{text-align:center;margin-bottom:1.5rem}.question-text{color:#1a1a1a;margin:0 0 1.5rem;font-size:clamp(1.5rem,4vw,2.2rem);font-weight:900}.highlight{color:#3b82f6;font-weight:900}.equation-display{justify-content:center;align-items:center;gap:1.5rem;margin:1.5rem 0;display:flex}.number,.operator,.equals{color:#1a1a1a;font-size:3rem;font-weight:900}.operator{color:#3b82f6}.answer-box{color:#3b82f6;background:#fff;border:4px solid #3b82f6;border-radius:12px;padding:1rem 2rem;font-size:3rem;font-weight:900;box-shadow:0 6px #3b82f6,0 10px 20px #3b82f61f}.options-grid{grid-template-columns:repeat(4,1fr);gap:1rem;max-width:1200px;margin:0 auto 1rem;display:grid}.option-card{text-align:center;cursor:pointer;background:#fff;border:4px solid #3b82f6;border-radius:16px;flex-direction:column;justify-content:center;min-height:150px;padding:2rem 1rem;transition:all .3s;display:flex;position:relative;transform:translateY(-3px);box-shadow:0 6px #3b82f6,0 10px 20px #3b82f61f}.option-card:hover{transform:translateY(-6px);box-shadow:0 9px #3b82f6,0 13px 26px #3b82f62e}.option-number{color:#fff;background:#3b82f6;border:4px solid #fff;border-radius:50%;justify-content:center;align-items:center;width:2.5rem;height:2.5rem;font-size:1.2rem;font-weight:900;display:flex;position:absolute;top:-12px;left:50%;transform:translate(-50%);box-shadow:0 4px 12px #3b82f64d}.option-value{color:#1a1a1a;font-size:4rem;font-weight:900}.option-card.correct{border-color:#10b981;animation:.5s correctPulse;box-shadow:0 8px #10b981,0 12px 24px #10b98133}.option-card.wrong{border-color:#ef4444;animation:.5s shake;box-shadow:0 8px #ef4444,0 12px 24px #ef444433}.option-card.show-correct{border-color:#10b981;box-shadow:0 8px #10b981,0 12px 24px #10b98126}@keyframes correctPulse{0%,to{transform:translateY(-3px)scale(1)}50%{transform:translateY(-3px)scale(1.05)}}@keyframes shake{0%,to{transform:translateY(-3px)translate(0)}25%{transform:translateY(-3px)translate(-10px)}75%{transform:translateY(-3px)translate(10px)}}.feedback-message{text-align:center;background:#fff;border:3px solid;border-radius:12px;justify-content:center;align-items:center;gap:.75rem;max-width:300px;margin:0 auto 1rem;padding:1rem 2rem;font-size:1.3rem;font-weight:800;display:flex;transform:translateY(-2px);box-shadow:0 4px,0 6px 12px #0000001a}.feedback-message.correct{color:#10b981;border-color:#10b981;box-shadow:0 4px #10b981,0 6px 12px #10b98133}.feedback-message.wrong{color:#ef4444;border-color:#ef4444;box-shadow:0 4px #ef4444,0 6px 12px #ef444433}.feedback-icon{font-size:1.5rem}.hand-status{background:#fff;border:3px solid #3b82f6;border-radius:12px;justify-content:space-between;align-items:center;max-width:250px;margin:0 auto;padding:.75rem 1.5rem;display:flex;transform:translateY(-2px);box-shadow:0 4px #3b82f6,0 6px 12px #3b82f61f}.status-label{color:#666;font-size:.9rem;font-weight:600}.status-value{color:#3b82f6;font-size:1.3rem;font-weight:900}.verifying-indicator{color:#f59e0b;margin-left:.5rem;font-size:.9rem;font-weight:700;animation:1.5s ease-in-out infinite verifyPulse}@keyframes verifyPulse{0%,to{opacity:1}50%{opacity:.5}}.confetti-container{pointer-events:none;z-index:9999;width:100%;height:100%;position:fixed;top:0;left:0;overflow:hidden}.confetti{opacity:0;width:10px;height:10px;animation:3s linear forwards confetti-fall;position:absolute;top:-10px}@keyframes confetti-fall{0%{opacity:1;top:-10px;transform:translate(0)rotate(0)}to{opacity:0;transform:translateX(calc(var(--random-x,0)*100px))rotateZ(720deg);top:100vh}}@media (max-width:768px){.subtraction-game-container{padding:1rem}.options-grid{gap:.75rem}.option-card{min-height:120px;padding:1.5rem .75rem}.option-value{font-size:3rem}.equation-display{gap:1rem}.number,.operator,.equals{font-size:2rem}.answer-box{padding:.75rem 1.5rem;font-size:2rem}}@media (max-width:640px){.options-grid{grid-template-columns:repeat(2,1fr)}}