That's neat - I actually started working on a JS Arkanoid game a long time ago for fun (I think I was going to call it "JS Arpanoid" ), but I never did finish it. Nice job!
If JS is capable of this, then why do all the JS effects have such a technical and uninspiring GUI?
GUI programming in JS is kinda awkward and tedious. Just doing graphics is easy enough but to do a full GUI you have to track mouse clicks/position and cross-reference against the coordinates of graphical entities. In short, it's just no fun at all.