Object: avoid compound squares.

A 7x7 square area is covered with square and oblong tiles.
Your task is ot rearrange the tiles such that the new tiling doesn't contain any 'compound squares'.
A compound squares is square area (smaller than 7x7) which is covered by more than one tile.
In the default setup, you can see a 3x3 compound square at the top left corner and another one at the top right corner.
There ia also a 2x2 compound square at the lower right corner.

To move a tile, click the from-position, then click the target position.
Note that the tiles may never overlap.
The wide rim around the main board is provided as a temporary storage while rearranging the tiles.

When you think you have succeeded, click the CHECK button.
If your solution is correct you will get a win message, otherwise a loss message.
In case of a loss the lower left (of the first compound square the system found) will be marked.

Solutions are attached.

Variants:
The more 1x1 squares are used, the harder the game is to solve.
The numbers in the variant titles are the numbers of 2x2 squares, dominoes and 1x1 squares used.