How To Ensure I Dont Apply Css

For some of the pages, I dont require css. Yii applies css according to what I have in main.php in my layout folder and also registers CSS as a part of bootstrap.

How can I avoid css being applied to some pages.

Maybe this will help http://stackoverflow.com/questions/17790797/preventing-a-specific-css-file-from-getting-loaded-in-yii