@import"https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap";:root{font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}*,*:before,*:after{box-sizing:border-box}html,body{margin:0;padding:0}html{scroll-behavior:smooth}:focus{outline:3px solid transparent}button:focus-visible{outline:3px solid var(--primary-color);outline-offset:2px}:root{--primary: #6366f1;--primary-hover: #4f46e5;--accent: #06b6d4;--success: #10b981;--error: #ef4444;--warning: #f59e0b;--bg-primary: #fafafa;--bg-secondary: #f4f4f5;--bg-tertiary: #ffffff;--surface: #ffffff;--surface-hover: #f8fafc;--text-primary: #0f172a;--text-secondary: #475569;--text-muted: #94a3b8;--border: #e1e5e9;--border-light: #f1f5f9;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .04);--shadow: 0 4px 8px rgba(0, 0, 0, .06);--shadow-lg: 0 8px 16px rgba(0, 0, 0, .08);--radius: 8px;--radius-lg: 12px;--transition: all .15s ease}.dark-theme{--primary: #818cf8;--primary-hover: #6366f1;--accent: #22d3ee;--success: #34d399;--error: #f87171;--warning: #fbbf24;--bg-primary: #0f172a;--bg-secondary: #1e293b;--bg-tertiary: #334155;--surface: #1e293b;--surface-hover: #334155;--text-primary: #f1f5f9;--text-secondary: #cbd5e1;--text-muted: #64748b;--border: #374151;--border-light: #4b5563;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .3);--shadow: 0 4px 8px rgba(0, 0, 0, .4);--shadow-lg: 0 8px 16px rgba(0, 0, 0, .5)}*{box-sizing:border-box;margin:0;padding:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:var(--bg-primary);color:var(--text-primary);line-height:1.5;-webkit-font-smoothing:antialiased}#root{max-width:1200px;margin:0 auto;padding:1rem;min-height:100vh}.sudoku-app{min-height:100vh;display:flex;flex-direction:column}header{display:flex;justify-content:space-between;align-items:center;padding:1.5rem 0;margin-bottom:2rem}h1{font-size:1.75rem;font-weight:700;background:linear-gradient(135deg,var(--primary),var(--accent));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;letter-spacing:-.025em}main{flex:1;display:flex;gap:2rem;align-items:flex-start;justify-content:center}footer{text-align:center;padding:2rem 0;color:var(--text-muted);font-size:.875rem}.icon{width:1.25rem;height:1.25rem}button{cursor:pointer;border:none;background:none;font-family:inherit;transition:var(--transition);outline:none}button:focus-visible{outline:2px solid var(--primary);outline-offset:2px}.game-container{display:flex;gap:2rem;width:100%;align-items:flex-start;justify-content:center}@media (max-width: 1024px){main{flex-direction:column;align-items:center;gap:1.5rem}.game-container{flex-direction:column;align-items:center}}@media (max-width: 768px){#root{padding:.5rem}header{padding:1rem 0;margin-bottom:1rem}h1{font-size:1.5rem}}.sudoku-container{display:flex;flex-direction:column;gap:1.5rem;align-items:center}.board-wrapper{width:400px;height:400px;background:var(--surface);border-radius:var(--radius-lg);padding:16px;box-shadow:var(--shadow);border:1px solid var(--border)}.sudoku-board{width:100%;height:100%;display:grid;grid-template-columns:repeat(9,1fr);grid-template-rows:repeat(9,1fr);gap:1px;background:var(--border);border-radius:var(--radius);overflow:hidden}.sudoku-cell{background:var(--surface);display:flex;align-items:center;justify-content:center;font-size:1.125rem;font-weight:500;cursor:pointer;transition:var(--transition);position:relative}.sudoku-cell:hover{background:var(--surface-hover)}.sudoku-cell.non-editable{cursor:default}.sudoku-cell.non-editable:hover{background:var(--surface-hover)}.sudoku-cell.selected{background:#6366f11f;position:relative}.sudoku-cell.selected:after{content:"";position:absolute;top:0;right:0;bottom:0;left:0;border:2px solid var(--primary);border-radius:2px;pointer-events:none}.sudoku-cell.related{background:#6366f10f}.sudoku-cell.same-digit{background:#f59e0b1f}.sudoku-cell.correct{background:#10b9811a}.sudoku-cell.incorrect,.sudoku-cell.conflict{background:#ef44441a}.border-top-thick{border-top:2px solid var(--text-muted)}.border-bottom-thick{border-bottom:2px solid var(--text-muted)}.border-left-thick{border-left:2px solid var(--text-muted)}.border-right-thick{border-right:2px solid var(--text-muted)}.cell-value{font-size:1.125rem;font-weight:600}.prefilled-value{color:var(--primary);font-weight:700}.user-value{color:var(--text-primary)}.user-value.correct{color:var(--success)}.user-value.incorrect,.user-value.conflict{color:var(--error)}.notes-grid{display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);width:100%;height:100%;font-size:.5rem;font-weight:500}.note-cell{display:flex;align-items:center;justify-content:center;color:var(--text-muted)}.number-input{display:flex;flex-direction:column;gap:1rem;width:400px}.note-toggle{display:flex;justify-content:center}.note-button{display:flex;align-items:center;gap:.5rem;padding:.5rem .75rem;border-radius:var(--radius);font-weight:500;font-size:.8125rem;background:var(--surface);color:var(--text-secondary);transition:var(--transition);box-shadow:var(--shadow-sm);border:1px solid 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var(--border)}.number-button:hover{background:var(--primary);color:#fff;transform:translateY(-1px);box-shadow:var(--shadow-sm);border-color:var(--primary)}.number-button.clear{background:linear-gradient(135deg,var(--error),#dc2626);color:#fff;border:none}.number-button.clear:hover{background:linear-gradient(135deg,#dc2626,#b91c1c);border:none}@media (max-width: 768px){.board-wrapper,.number-input{width:min(90vw,320px)}.board-wrapper{height:min(90vw,320px);padding:12px}.sudoku-cell,.cell-value{font-size:1rem}.number-pad{padding:.75rem;gap:.375rem}.number-button{padding:.625rem;font-size:.8125rem}.note-text{display:none}}@media (max-width: 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var(--border)}.timer .icon{color:var(--primary);width:1rem;height:1rem}.difficulty-selector{display:flex;flex-direction:column;gap:.75rem}.difficulty-selector span{font-weight:500;font-size:.75rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.05em;text-align:center}.input{display:flex;background:var(--bg-secondary);border-radius:var(--radius);padding:4px;border:1px solid var(--border);cursor:text}input:disabled{cursor:not-allowed}.chk-cont{display:flex;align-items:center;justify-content:center;cursor:pointer;width:auto;height:auto}.checkbox{margin:10px;border:none}.difficulty-buttons{display:flex;background:var(--bg-secondary);border-radius:var(--radius);padding:4px;border:1px solid var(--border)}.difficulty-buttons button{flex:1;padding:.5rem .75rem;border-radius:calc(var(--radius) - 4px);font-weight:500;font-size:.8125rem;color:var(--text-secondary);transition:var(--transition)}.difficulty-buttons button:hover{color:var(--text-primary);background:#6366f114}.difficulty-buttons button.active{background:var(--surface);color:var(--primary);box-shadow:var(--shadow-sm);border:1px solid var(--border)}.game-actions{display:flex;flex-direction:column;gap:.5rem}.action-button{display:flex;align-items:center;justify-content:center;gap:.5rem;padding:.75rem 1rem;border-radius:var(--radius);font-weight:500;font-size:.8125rem;background:var(--surface);color:var(--text-primary);transition:var(--transition);box-shadow:var(--shadow-sm);border:1px solid var(--border)}.action-button:hover{transform:translateY(-1px);box-shadow:var(--shadow);border-color:var(--primary)}.action-button .icon{width:1rem;height:1rem}.new-game{background:linear-gradient(135deg,var(--primary),var(--primary-hover));color:#fff;border:none}.new-game:hover{background:linear-gradient(135deg,var(--primary-hover),#3730a3);border:none}.reset{background:linear-gradient(135deg,var(--warning),#d97706);color:#fff;border:none}.reset:hover{background:linear-gradient(135deg,#d97706,#b45309);border:none}.solve{background:linear-gradient(135deg,var(--success),#059669);color:#fff;border:none}.solve:hover{background:linear-gradient(135deg,#059669,#047857);border:none}@media (max-width: 1024px){.game-controls{width:100%;max-width:400px}}@media (max-width: 768px){.game-actions{flex-direction:row;gap:.5rem}.action-button{flex:1;font-size:.75rem;padding:.625rem .5rem}.button-text{display:none}}