This is a fun submission, after all this genre is tried and true to be addicting. Although it does get repetitive after a while. I think the remedy the repetitiveness you could maybe have the timer be varying. Rather than just resetting the timer to full no matter what you could do something like if you only match 3 then it only adds 2 seconds to the timer but if you match 5 it adds 10 seconds. Or something like that. That way you can prevent the player from just matching 3s all day
If you really wanted to get fancy with it, then it would also be nice if the game had a system in place to assure that there is always at least one switch you can do to make a match, that way the player is never just forced to lose.
Good submission!