[protonfish]

Here is an example of a generic HTML doc that changes layout by changing only CSS: http://protonfish.com/csssatori/ It's been a few years since I wrote it and it was just a prototype, but it should be a good example of what you asked to see.

Separating content and layout takes a little effort to learn but I assure you it is possible and effective. In my opinion, grid-based layouts are table-based layouts with a coat of paint.