Find out the hidden colors: Drag-and-drop 4 colors from the left to the first empty row and click on "Check".
If you are using a mobile device, first tap on the chosen color and then tap on a position.
Check marks: Grey => incorrect color, White => correct color but incorrect position, Black => both color and position are correct.
There is no repetition among hidden colors. There is no relation between the positions of the guessed colours and the check marks.
This site is under development, there might be problems.