which css framework is the best??

Hello Guys, i need to know which css framework is the best for responsive website??? if you have idea about it, give me full suggestion with proper reason..

Thanks...

Check out the Twitter Bootstrap. There's a ton of support for it and there are lots of themes and elements readily available. Whenever I'm prototyping a site I use it.

http://getbootstrap.com/2.3.2/

Hello,
It depends. Twitter Bootstrap is very popular solution, and I've tried it. Very powerful, enourmous amount of components, js scripts.
It's got even preprocessors.
I've heard that Zurb Foundation (last update) is pretty much as strong as bootstrap.
Conclusion: these are two most popular front-end IMO.