First alternating color question

[Gayble]

Hi everyone,

I have this code for the background of the first alternating color on my Main CSS:

#6E6F71 url(night/descgradient.gif) repeat-x top left

Just one problem:
http://www.goompy.com/forum/showthread.php?p=1

How can I make the gradient repeat so that it goes all the way down all the time? (I'm talking about the light grey gradient that you see under the username)

I appreciate your help.