[ This is a challenging rubic-like puzzle ]
There is a red 'symmetry transformer' at the centre of each square.
If you click on any of its lines, the square will reflect or 'flip' about that line.
If you click on its red centre-diamond the square will rotate 90 degrees. Try it.
There are also extra symmetry transformers between the squares.
Click on them to work out which group of squares each controls.
Now try this: Use the symmetry transformers to arrange the square so that the pattern as a whole has
horizontal and vertical symmetry.
(You can check if it has symmetry by clicking the horizontal and vertical lines on the central symmetry transformer.
If it does, then flipping the pattern should produce exactly the same pattern, so you shouldn't see any difference.)
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