private void New_Game(object sender, RoutedEventArgs e)
 {
     IsGameStarted = true;
     for (int i = 0; i < 9; i++)
     {
         for (int j = 0; j < 9; j++)
         {
             Template.SudokuBoard[i, j] = Template.SudokuTemplate[i, j];
             Board.Cells[i, j].CellTextBox.Background = Brushes.WhiteSmoke;
         }
     }
     Board.FillBoard();
     Board.Counter++;
 }