Now that even Microsoft has given up on IE10, it seems like a good time to actually learn more about flexbox. Some helpful sites:

A Complete Guide to Flexbox

A Visual Guide to CSS3 Flexbox Properties

The biggest stumbling block I ran into was trying to implement a layout using justify-content: space-between with remainder elements in the last row. This is the best workaround I’ve seen: http://codepen.io/diana_aceves/pen/KVGNZg.