Fun idea - I played until I got around 1000 score.
I like how you made the player fall slower by default - one of my problems with games where you fall down is that you move too quickly and have little time is given to react, but I don't feel that way here (and you're given an option to go fast as well). I think the movement was done well for a game of this type.
One small critique is that the foreground/background separation could be a little bit better in some places - for example the spider is the almost same color as the center of the screen, and the cyan color in particular popping in and the background sometimes distracts my eyes from the webs.
As other people said, good use of parallax to create a unique environment.