Freebie: Flexgrid - Dead Simple Responsive Flexbox Grid System

Flexgrid

A dead-simple, bare bones responsive grid to help you get your layouts looking sharp quickly. It only cares about laying out your content, so you can style your websites and applications however you like, without having to worry about creating a custom grid system.

Flexgrid is a responsive 12 column grid, with sizing classes available for elements spanning 1 through 12 columns, so you can easily mix and match column sizes. If you don't need all 12 columns, helper classes are included to center and/or reverse your columns.

Check it out