Last April I spoke at WordCamp London about alternatives to CSS frameworks like Bootstrap, Foundation, etc.
Here's the video of the talk, and you can also see the slides online. If you would rather read a written version of this talk, you can checkout my article at Mozilla's Hacks blog.
I loved this conference, so go watch other talk videos as well. I specially enjoyed Sarah Semarks's talk about using SVG images instead of icon webfonts. And it was very refreshing seeing a lot of different people attending the conference!