Needs improvements
Not a bad game, but it requires some fixes:
Time bar needs to go down faster the longer you go on. Otherwise even moderately skilled players will go on forever.
You should allow people to swap two pieces even if they don't make a match. Switch them back afterward if they don't match, of course, but don't just turn off the first piece.
Clicking was a bit choppy. Sometimes it worked, sometimes it didn't. I assume this has something to do with the framerate.
Make a leaderboard, otherwise games like this are pretty pointless.
Getting multiple matches in a row from a single switch should get extra points. As it is now you get the same points when you get chains as if you were to get each match separately.
Other than those things, graphics were alright, sounds were fine.