I took me far longer than it should have done to figure out that I need to press the left and right keys on my keyboard, rather than use the mouse.

The shade of grey used for the background makes it very hard to read black text, so when both options are written in black I just guess. Sadly I don't know what a good alternative would be, as the range of colours you are using means you'd be hard pressed to find something good. A light-ish brown background may do the trick.

In general, it's an annoying game to play and I probably wouldn't spend too long at it. adding a relaxed mode with no time limit would make a nice addition.