Looking for lightweight responsive CSS framework supporting max width 968px

[perzefi]

I have been looking into using a css framework for my next project. I would like to use a css framework that is responsive and should have a max-width: 968px also it should be lightweight system (only grids), not requiring buttons, navigation etc. Are there any recommendations on css frameworks that I should use, the problem that I seem to come across is that the frameworks are generally set to a predefined size such as 960px and something seems to break whenever I make changes to support this 968px size (it may just be my lack of experience of using frameworks and lack of understanding). I am looking for recommendations on which css framework to use, and also any help on setting it up for the max width 968px;Thanks in advance.