A project I am working on needs to integrate a new feature using HTML5 and CSS. The requirement is that each individual user of the system can pick one of several pre-configured layouts to view content. So users might pick one of the following three layouts:

- Content is different based on the layout the user chooses. (e.g. D is in layout 1 but not in layout 3)
- Each content block will have its own css
- The css for each content block will be same regardless of position
- There may be more layouts in the future.
I have some ideas in mind and have found some ideas searching Google, but I can't seem to find the right things to ask Google to get where I need to be.
My Ideas:
- Have a style sheet for each layout and change the style sheet based on the users selection. Always include the styles for each content block on the page.
- Build the css for each user on the server and only send the css needed for that layout
Thanks!