Ask HN: Responsive framework or addon with good layout?

I am trying to get better at frontend UI design. I have been working with Foundation 5 framework for a while as I like the mobile first approach. I like their grid, but it seems difficult to be able to place items within a container. Is there another library or framework I can use with Foundation to provide better layout within containers? I did not want to try to go full custom css as it is incredibly hard to support the different mobile browsers.