CSS update: grid-template-area for Our Commitments

[rjkerrison]

Use grid-template-area for Our Commitments and have a single grid of 11 columns with separate rows.

I think there's a much better way to do this using grid-template-area so we can set up the 11 columns divided into 4 areas in the 5, 6 / 6, 5 pattern. I plan to push up changes to this branch to show this.

Originally posted by @rjkerrison in #103 (comment)