*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}code{font-family:source-code-pro,Menlo,Monaco,Consolas,Courier New,monospace}.tic-tac-toe-game{display:flex;flex-direction:column;align-items:center;gap:20px;width:100%;max-width:480px;margin:0 auto;padding:30px;background:#fff;border-radius:15px;box-shadow:0 10px 40px #0000004d;color:#333}.setup-controls{display:flex;flex-wrap:wrap;justify-content:center;align-items:stretch;gap:15px;width:100%}.setup-group{flex:1 1 160px;min-width:140px;margin:0;padding:12px 15px;border:2px solid #e9ecef;border-radius:10px;background:#f8f9fa}.setup-group:disabled{opacity:.55}.setup-group legend{padding:0 6px;font-size:.9rem;font-weight:700;color:#667eea}.option-row{display:flex;justify-content:center;gap:10px}.option-row label{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:44px;padding:0 14px;border:2px solid #dee2e6;border-radius:8px;font-size:1.05rem;font-weight:600;color:#333;cursor:pointer;transition:all .2s ease}.option-row label:hover{border-color:#667eea}.option-row label:has(input:checked){border-color:#667eea;background:#667eea;color:#fff;box-shadow:0 2px 8px #667eea66}.setup-group:disabled .option-row label{cursor:not-allowed}.option-row input[type=radio]{width:18px;height:18px;accent-color:#667eea;cursor:inherit}.setup-summary{flex-basis:100%;margin:0;text-align:center;font-size:.95rem;color:#868e96;font-weight:600}.board{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;width:min(100%,360px);aspect-ratio:1;padding:10px;background:linear-gradient(135deg,#667eea,#764ba2);border-radius:12px;box-shadow:0 6px 20px #667eea59}.cell{min-width:44px;min-height:44px;width:100%;aspect-ratio:1;display:flex;align-items:center;justify-content:center;font-size:clamp(1.8rem,12vw,3rem);font-weight:700;line-height:1;color:#333;background:#fff;border:none;border-radius:8px;cursor:pointer;transition:background .15s ease,transform .15s ease,box-shadow .15s ease}.cell:hover:not(:disabled){background:#eef1ff;transform:translateY(-1px)}.cell--focused,.cell:focus-visible{outline:3px solid #764ba2;outline-offset:2px;box-shadow:0 0 0 4px #764ba259}.cell:focus{outline:3px solid #764ba2;outline-offset:2px}.cell--winning{background:linear-gradient(135deg,#51cf66,#37b24d);color:#fff;box-shadow:0 0 0 3px #37b24d66}.cell--winning:hover:not(:disabled){background:linear-gradient(135deg,#51cf66,#37b24d)}.status-bar{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:12px;width:100%;min-height:48px}.turn-indicator{font-size:1.2rem;font-weight:700;color:#333}.result-banner{padding:10px 18px;font-size:1.2rem;font-weight:700;border-radius:10px}.result-banner--won{color:#2b8a3e;background:#d3f9d8}.result-banner--draw{color:#495057;background:#e9ecef}.difficulty-badge{padding:4px 12px;font-size:.8rem;font-weight:700;text-transform:capitalize;color:#fff;background:linear-gradient(135deg,#667eea,#764ba2);border-radius:999px}.sr-status{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);clip-path:inset(50%);white-space:nowrap;border:0}.score-panel{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;width:100%}.score{flex:1 1 90px;min-width:80px;padding:10px 12px;text-align:center;font-size:1.05rem;font-weight:700;border-radius:10px;background:#f8f9fa;border:2px solid #e9ecef}.score--x{color:#5f3dc4;border-color:#d0bfff}.score--o{color:#1971c2;border-color:#a5d8ff}.score--draws{color:#495057}.game-controls{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;width:100%}.game-controls button{flex:1 1 140px;min-width:120px;min-height:44px;padding:12px 20px;font-size:1rem;font-weight:700;color:#fff;border:none;border-radius:10px;cursor:pointer;background:linear-gradient(135deg,#667eea,#764ba2);transition:transform .2s ease,box-shadow .2s ease}.game-controls button:hover{transform:translateY(-2px);box-shadow:0 6px 20px #667eea80}.game-controls button:focus-visible{outline:3px solid #764ba2;outline-offset:2px}@media(max-width:480px){.tic-tac-toe-game{padding:18px;gap:16px}.setup-group{flex-basis:100%}.turn-indicator,.result-banner{font-size:1.05rem}}@media(max-width:360px){.tic-tac-toe-game{padding:12px}.board{gap:6px;padding:6px}.score,.game-controls button{flex-basis:100%}}.App{display:flex;flex-direction:column;align-items:center;min-height:100vh;padding:24px 16px 40px;background:linear-gradient(135deg,#667eea,#764ba2);color:#333}.app-header{text-align:center;margin-bottom:20px}h1{color:#fff;margin-bottom:6px;font-size:2.5rem;font-weight:800;letter-spacing:-.5px;text-shadow:0 2px 8px rgba(0,0,0,.25)}.app-subtitle{color:#ffffffeb;font-size:1.05rem;margin:0;font-weight:500}.app-main{width:100%;display:flex;justify-content:center}.game-info{width:100%;max-width:520px;margin-top:32px;display:flex;flex-direction:column;gap:16px;text-align:left}.info-card{background:#fffffff2;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);padding:20px 24px;border-radius:12px;box-shadow:0 8px 24px #00000026}.info-card h2{font-size:1.15rem;color:#4338ca;margin-bottom:10px;font-weight:700}.info-card p{font-size:.92rem;line-height:1.55;color:#4b5563;margin:0}.info-card ol,.info-card ul{font-size:.92rem;line-height:1.6;color:#4b5563;padding-left:20px;margin:0}.info-card li{margin-bottom:4px}.info-card li:last-child{margin-bottom:0}kbd{display:inline-block;padding:2px 6px;font-size:.8rem;font-family:inherit;font-weight:600;color:#1e293b;background-color:#f1f5f9;border:1px solid #cbd5e1;border-radius:4px;box-shadow:0 1px 2px #00000014}@media(max-width:768px){.App{padding:16px 12px 32px}h1{font-size:2rem}.app-subtitle{font-size:.95rem}.info-card{padding:16px 18px}}@media(max-width:480px){h1{font-size:1.7rem}.app-subtitle{font-size:.88rem}}