Minor fixes
More than 70 of classic and new Sudoku designs:
🔥 Different Sudoku types: Classic, Diagonal, Hyper, More-or-Less
🔥 Different Sudoku shapes: Single, Double, Triple, Zigzag and Samurai
🔥 Different Sudoku sizes: 4x4, 6x6, 9x9, 12x12 and 16x16
Multiple difficulty levels: from beginners to masters.
