hover joys

The next thing I really want in my navbar was a black box to pop up around the button when i hover my mouse over it. I had read in the WebDesign text hover command for the css styling where a background colour could be changed at hover. I simply coppied this and instead of a background colour change i used a black border of 1 px which i had seen done on the online lectures many many times. too easy.

Thats' it working in my webpage navbar.