That can be done, but the architecture of our Layout Manager makes it less abstract. The added flexability that comes with this feature also creates some minor challenges in these typically easy design styles. If you look at most themes that have design features like this it’s a static template in the theme that you can’t modify or control in any way other an possibly a few settings like the color of the background or placement of the sidebar (left/right) and maybe the number of them. By contrast our themes let you totally control the design, style, layout, structure and more of every single page and content area of your website.
So, now that I’ve totally over explained this, if you can show me the page you are working on I can use the browser inspector to get the necessary layout classes for you to use in order to make this style possible. It is completely layout specific because of the things I described above, which makes it more challenging for us to include these styles in a theme and it’s the reason you don’t see that type of layout in the demo. It wouldn’t translate to your site exactly but it can absolutely be done on an individual site by site, layout by layout basis.
Interesting side note (at least in my mind). I’m planning to add a custom CSS feature to the layout manager making it possible to have custom styles associated with specific layouts, besides the existing skin selector, which should bridge the gap I was trying to describe above. It would be a very powerful addition to that extension.
So, shoot us a link to the page where you want to do that and I’ll get you what you need. 
