First, you need to look at the console, because you have some errors there.
I am unable to give feedback, because after trying to play the game 8 times, after clicking Start, something different would happen each time. For example, one time, on the first round the same button blinked twice. On another go at the game on the first round, all four buttons lit up in sequence.
You definitely need to do several tests to see how the game plays out. Let me know when you get some of the kinks worked out and I will try again.
As far as visually, I noticed on this project and any other project you are using a toggle switch, the text on the left and right sides of the switch are not lined up vertically. Also, I would try and change the background color from blue (when switched to the right) to be the same grey as when switched to the left. That blue background sticks out like a sore thumb on your projects.