Toroidal-Sudoku

A perfect Toroidal-Sudoku is here for all sudoku lovers with amazing 5 different difficulty options. Options 1 to 5 varies from very simple, easy to hard and toughest game play.
Rules-
The objective of sudoku is to enter a digit from 1 to 'size of grid' in each cell, in such a way that:
a) Each horizontal row contains each digit exactly once
b) Each vertical column contains each digit exactly once
c) Each thick outlined coloured region should contain digits exactly once.
Note-for 9x9 grid , each 3x3 subgrid contains each digit exactly once
• Different grid sizes like 5x5, 6x6, 7x7, 8x8, 9x9
• More than 1,00,00,00,00,00,000 puzzles.
• NO puzzle gets repeated
• Many free themes
• Intelligent hints
• Selected digit highlighting
• Incorrect entry highlighting
• 16 different difficulty options
• Undo and Redo
So get ready to be puzzled...