It bounces because you have a fake bounce. See this article: http://www.emanueleferonato.com/2007/03/04/create-a-flash-draw-game-like-line-rider-or-others-part-4/
I'm sorry, but this is exactly like some tutorials on emanueleferonato (Create a flash drawing game parts 1 and 3). If you want to make a game, it needs some kind of idea. You basically copy-pasted from a tutorial, changed the colour of the line, and added your name to the bottom-right. I won't flag but I will rate 1/5. Good luck on future games.
Nevermind. I think when you're scored on, your goal should shrink. Very creative approach to making the game challenging. AI does need a little work though.
MY ARMS ARE TIRED. I used two mice with two arms and managed to beat it. The restart button needs work; there shouldn't be a white box around the text if it's on a grey button ;)
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