Each subsection contains four numbered pieces which may be pivoted within its own section. As the chosen section is rotated, all orthogonal subsections all also rotated - but in reverse fashion.
To complete the puzzle successfully, the ending layout needs to be right side up. That is, the numbers will be read normally and the squares will also apppear as black with white lettering.

The four different colours (depending on orientation) can also help to guide you. The Freeplay variant(s) doesn't have a win-condition applied. Occasionally, a start-up move may randomly be reversed.