Urgent! help - How to apply styles to onMouseover text descriptions

I am building a CSS hover menu with onMouseover text descriptions. The code was originally taken from http://www.javascriptkit.com/javatutors/crossmenu2.shtml

I would like to style the text that appears onMouseove, but I have no javascript experience. I have used my CSS styling knowledge and come up with this:

I would love some feedback; someone with knowledge to check wether what I have done is actually okay! I mean the styles do show, but is the javacript correct?!

I look forward to hearing from someone. Any feedback much appreciated.