A CodePen by Johan van Tongeren. Fluid Grid Using Text-align: Justify - A new technique for responsive grids I've been working on which uses inline-block and text-align: justify. 

Take a look at this article for an explanation of the fundamentals of the technique:

http://www.barrelny.com/blog/text-align-justify-and-rwd/

Essentially, margins are calculated by the browser and never specified in the CSS. This saves a lot of tedious work! Also by not having to use floats, clearfixes, or nth-child, we avoid many common problems associated with more traditional methods.