Sudoku

Pointer controls:

• Click a cell to select it.
• Click 1-9 on the number pad to fill the selected editable cell.
• Use the X button to clear the selected cell or the die button to generate a new puzzle.
• In the selected empty cell, hover a 3x3 mini-position to preview its candidate, then click to toggle it.

Optional keyboard shortcuts:

• 1-9: set a value in the selected editable cell.
• Shift+1-9 or Ctrl+1-9: toggle candidate marks.
• 0, Backspace, or Delete: clear selected editable cell.
• Arrow keys: move selection.
• R, N, or Enter: generate a new random puzzle.