Change blog's short description

Hi guys
I am going nuts with something.
The address of my blog is http://warm-up-lap.com

I want to chage my blog’s short decription (appearing on the top right, the one that says “De motos y sobre motos”

I have edited the Blog’s name (Warm Up Lap), but I haven’t figured out how to change the short description in the style.css
Here is the code:

[CSS code moderated – the link to your site is enough to access the stylesheet]

THANKS!!