Adding CSS prefixes for various browsers takes time; and many designers have to write the appropriate prefix for each, mostly for new CSS3 features. Not exactly a productive use of time. Sure, eventually you’ll have memorized them all, but it still usually means writing eight or ten lines of CSS code instead of two or three.
But if you’re using a Python framework, you can just use CSSPrefixer instead. Write your CSS code as you normally would, and let CSSPrefixer insert all of the necessary prefixes for various browsers. And then use the time you save for something that’s actually productive. (cc)
Read more by: http://cssprefixer.appspot.com/