Black screen when I tried to go fullscreen.

I opened the game and it ran smoothly for about 5 minutes up until i went into settings and tried to make the game full screen. I had to turn my mac off to get out of the application. i tried to open Minecraft again but after displaying the "MAJONG" logo it turned into the same black screen. I have deleted and re-downloaded the application multiple times but nothing I try seems to work.