The Tokyo JumpStart provides the easiest of solutions for changing the amount of columns on a page - you simply need to add a class to the body tag and the CSS takes care of everything else for you!
The Tokyo JumpStart includes the following tutorials:
- Centering a Wrapper - by John Gallant & Holly Bergevin
- Create Columns with Floats by Zoe Gillenwater
- Do You Want To Do That With CSS? - Floating Clear- by John Gallant & Holly Bergevin
- CMX Internet Explorer Conditional Comment Extension by Paul Davis
- Making CC & DT style sheets work for you by Adrian Senior
- CSS Tricks: Using Descendant Selectors to Control the Number of Columns by Stephanie Sullivan
There are some great tutorials for you to work through in that list, as well as a great extension for creating the conditions for using conditionally commented style sheets that feed styles to the various versions of Internet Explorer.
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