#sudoku-container{display:flex;flex-direction:column;align-items:center}#sudoku-grid{display:grid;grid-template-columns:repeat(9,45px);grid-template-rows:repeat(9,45px);gap:1px;background:#2d3748;border:3px solid #2d3748;border-radius:8px;margin:20px 0}.sudoku-cell{background:#fff;display:flex;align-items:center;justify-content:center;font-size:18px;font-weight:600;cursor:pointer;transition:all .2s ease;position:relative}.sudoku-cell:hover{background:#f3f4f6}.sudoku-cell.selected{background:#dbeafe;box-shadow:inset 0 0 0 2px #3b82f6}.sudoku-cell.given{background:#f9fafb;color:#374151;font-weight:700}.sudoku-cell.error{background:#fef2f2;color:#dc2626}.sudoku-cell.highlight-row,.sudoku-cell.highlight-col,.sudoku-cell.highlight-box{background:#f0f9ff}.sudoku-cell.completed-box{background:#dcfce7;border-color:#16a34a;color:#15803d;font-weight:600}.sudoku-cell.highlight-number{background:#fef3c7!important;font-weight:700!important;color:#92400e!important;border-color:#f59e0b!important}.sudoku-cell:nth-child(3n){border-right:2px solid #2d3748}.sudoku-cell:nth-child(n+19):nth-child(-n+27),.sudoku-cell:nth-child(n+46):nth-child(-n+54){border-bottom:2px solid #2d3748}#number-controls{display:flex;gap:8px;margin-top:20px;padding:12px 16px;background:#fffffff2;border-radius:12px;box-shadow:0 4px 16px #0000001a;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid rgba(0,0,0,.1)}.number-btn{background:linear-gradient(135deg,#667eea,#764ba2)!important;color:#fff!important;border:none;border-radius:8px;padding:12px 16px;font-size:16px;font-weight:600;cursor:pointer;box-shadow:0 3px 12px #667eea66;transition:all .2s ease;min-width:44px;min-height:44px;display:flex;align-items:center;justify-content:center;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent;-webkit-appearance:none;-moz-appearance:none;appearance:none}.number-btn:hover{transform:translateY(-2px);box-shadow:0 6px 16px #667eea66}.number-btn:active{transform:translateY(0);box-shadow:0 2px 8px #667eea4d;background:linear-gradient(135deg,#5a67d8,#6b46c1)!important;color:#fff!important}.number-btn:focus{outline:none;box-shadow:0 0 0 3px #667eea80;background:linear-gradient(135deg,#667eea,#764ba2)!important;color:#fff!important}.number-btn:focus:not(:active){background:linear-gradient(135deg,#667eea,#764ba2)!important;color:#fff!important}.erase-btn{background:linear-gradient(135deg,#ef4444,#dc2626)!important;box-shadow:0 3px 12px #ef444466;color:#fff!important}.erase-btn:hover{box-shadow:0 6px 16px #ef444466}.erase-btn:active{background:linear-gradient(135deg,#dc2626,#b91c1c)!important;color:#fff!important}.erase-btn:focus{background:linear-gradient(135deg,#ef4444,#dc2626)!important;box-shadow:0 0 0 3px #ef444480;color:#fff!important}.erase-btn:focus:not(:active){background:linear-gradient(135deg,#ef4444,#dc2626)!important;color:#fff!important}@media (max-width: 768px){#sudoku-grid{grid-template-columns:repeat(9,44px);grid-template-rows:repeat(9,44px);gap:1px}.sudoku-cell{font-size:18px;font-weight:600;min-height:44px;min-width:44px;touch-action:manipulation}.sudoku-cell:active{transform:scale(.95);transition:transform .1s ease}#number-controls{gap:6px;margin-top:16px;padding:10px 12px;flex-wrap:nowrap;overflow-x:auto}.number-btn{min-width:40px;min-height:40px;padding:8px 12px;font-size:15px;flex-shrink:0}}@media (max-width: 480px){#sudoku-grid{grid-template-columns:repeat(9,38px);grid-template-rows:repeat(9,38px)}.sudoku-cell{font-size:16px;min-height:38px;min-width:38px}#number-controls{gap:4px;margin-top:12px;padding:8px 10px;flex-wrap:wrap;justify-content:center;max-width:320px}.number-btn{min-width:36px;min-height:36px;padding:6px 10px;font-size:14px;flex:0 0 calc(20% - 4px)}}@media (hover: none) and (pointer: coarse){.sudoku-cell{cursor:pointer;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent;touch-action:manipulation}.sudoku-cell:hover{background:#3b82f61a}.number-btn{cursor:pointer;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent;touch-action:manipulation}.number-btn:active{transform:scale(.95);transition:transform .1s ease}#sudoku-container{position:relative;touch-action:manipulation}#sudoku-grid{touch-action:manipulation;user-select:none;-webkit-user-select:none;-webkit-touch-callout:none}}