Good game
Graphics: Good graphics.
Style: A guy goes and buys a burger and the burger turns into a portal? Should explain the plot more. Also, during the game I got the deeling that something just doesn't mesh together. I dunno, but I just get the feeling that something is not right.
Sound: You should use a longer loop for the backgound music. It is too short and gets annoying really quickly - had to turn it off within the first minute.
Interactivity: The spring thing is kinda glitchy. When I just regularly jump on it - don't press up while jumping - and then press up at the peak of the jump I can do a regular jump in midair.