When you click any of the blue buttons, the tiles rotate around it.
Click, for example, the upper left button, then the button to the right of it, and then try to restore the original position of the game board.
If you can't do this, click the right button in the bottom row.
Every time you click the second button from the right in the bottom row, 4 tiles rotate around one random blue button.
You can set the difficulty of the game with the second button from the left in the bottom row.
Depending on the number on this button, the tiles of the top two rows, the top three rows, or all the tiles of the game board will be shuffled.