Grid layouts in flex box

Some colleagues brought up layouts today. The team just started using flex box instead of Bootstrap’s grid (yey!), and someone mentioned this article:

Don’t use flexbox for page layout

So, I created a pen to try and prove Jake wrong (no offense, Jake):

My pen

By using flex-basis, I effectively set a min width for the containers that shouldn’t grow. Then the main container fills the rest of the space. For content in the main container, you could just have a max-width container.