Meghneu, doing that is a little bit easy but it requires a lot of modifications for template_css.css file. I can only suggest you to carefully edit these CSS Selectors:
/* main body width */
#ja-container {
width: 770px;
...
}
/* main column width when there're 3 columns */
#ja-content {
...
width: 432px;
...
}
/* main column width when there're 2 columns */
#ja-content-full-left {
...
width: 585px;
...
}
/* main column width when there're 2 columns */
#ja-content-full-right {
...
width: 585px;
...
}
/* main column width when there's only 1 column */
#ja-content-full {
...
width: 730px;
}
/* left column width */
#ja-leftcol {
width: 150px;
...
}
/* right column width */
#ja-rightcol {
width: 150px;
...
}
Hope this information will be usefull for you, my friend!
