Front page main/inset alignment

Hi
In my front page the articles are restricted and leave lots of space in the right side. The undesired space is noted in the atttached gif.
Can u pls advise how to enlarge the witdh of the articles?
Thank you in advance

Better send your link, I can not see anything on your picture it is too small.

www.smarties.gr
look at the categories in the leaving lot of space in the right hand side
thank u

add this to template_css.css on the bottom:

.content_pad .blog{
width:470px;
}

Done, thank you very much Ivan