:root{font-family:Comic Neue,cursive;line-height:1.5;font-weight:700;color-scheme:light;color:#213547;background-color:#f9f4ff;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}*{box-sizing:border-box}body{margin:0;display:flex;place-items:center;min-width:320px;min-height:100vh}#app{max-width:800px;margin:0 auto;padding:2rem;text-align:center}h1{font-size:3.2em;color:#7b68ee;text-shadow:2px 2px 4px rgba(0,0,0,.2);margin-bottom:1rem}.container{display:flex;flex-direction:column;gap:20px;align-items:center}.level-selection{display:flex;flex-direction:column;gap:15px;max-width:400px;width:100%}.level-button{padding:12px 20px;font-family:Comic Neue,cursive;font-size:1.2rem;font-weight:700;background:linear-gradient(145deg,#ffd79a,#ffb347);border:3px solid #ff9800;border-radius:15px;cursor:pointer;transition:transform .2s,box-shadow .2s;box-shadow:0 4px 6px #0000001a}.level-button:hover{transform:translateY(-3px);box-shadow:0 6px 8px #00000026}.level-button:active{transform:translateY(1px);box-shadow:0 2px 4px #0000001a}.game-container{display:flex;flex-direction:column;align-items:center;gap:25px;max-width:600px;width:100%}.progress-bar{width:100%;height:15px;background-color:#e0e0e0;border-radius:10px;overflow:hidden}.progress-fill{height:100%;background:linear-gradient(to right,#4caf50,#8bc34a);transition:width .5s}.equation{font-size:4rem;background-color:#fff;padding:20px 40px;border-radius:20px;box-shadow:0 8px 25px #0000001a;display:flex;align-items:center;justify-content:center;gap:15px}.equation-number{display:inline-block;min-width:70px;text-align:center}.answer-input{width:100px;font-size:4rem;text-align:center;border:3px dashed #7b68ee;border-radius:15px;padding:5px;font-family:Comic Neue,cursive;font-weight:700;color:#213547;outline:none}.answer-input:focus{border-color:#4caf50;box-shadow:0 0 10px #4caf5080}.check-button{padding:15px 40px;font-size:1.5rem;font-family:Comic Neue,cursive;font-weight:700;background:linear-gradient(145deg,#50c878,#4caf50);border:none;color:#fff;border-radius:15px;cursor:pointer;transition:transform .2s;box-shadow:0 4px 8px #0003}.check-button:hover{transform:scale(1.05)}.check-button:active{transform:scale(.98)}.feedback{font-size:2rem;height:60px;display:flex;align-items:center;justify-content:center}.next-button{padding:12px 30px;font-size:1.2rem;font-family:Comic Neue,cursive;font-weight:700;background:linear-gradient(145deg,#738adb,#5d76e7);border:none;color:#fff;border-radius:15px;cursor:pointer;transition:transform .2s;box-shadow:0 4px 8px #0003}.next-button:hover{transform:scale(1.05)}.next-button:active{transform:scale(.98)}.result-screen{display:flex;flex-direction:column;align-items:center;gap:25px}.result-title{font-size:2.5rem;color:#7b68ee}.score{font-size:3.5rem;color:#4caf50}.play-again-button{padding:15px 40px;font-size:1.5rem;font-family:Comic Neue,cursive;font-weight:700;background:linear-gradient(145deg,#ff9800,#ff6f00);border:none;color:#fff;border-radius:15px;cursor:pointer;transition:transform .2s;box-shadow:0 4px 8px #0003}.play-again-button:hover{transform:scale(1.05)}.play-again-button:active{transform:scale(.98)}.hidden{display:none!important}.emoji{font-size:40px;position:fixed;animation:fall 2s linear forwards;z-index:1000}@keyframes fall{0%{transform:translateY(-50px) rotate(0);opacity:1}to{transform:translateY(100vh) rotate(360deg);opacity:0}}@media (max-width: 600px){.equation{font-size:3rem;padding:15px 25px}.answer-input{width:80px;font-size:3rem}.check-button,.play-again-button{padding:12px 30px;font-size:1.3rem}}