It’s simple and clean, valid xhtml transitional and css.
The centerblocks in this theme surround the Content of xoops modules so you might play with blocksettings if you want. If you know a bit CSS you may float the centerblocks left and right but you will know what you want.
This theme allows you to display One, Two or No sideblock by settings in blockadmin. I love to show a forum with full width of a theme.