This is based on cfx's solution, but rather than setting the font size to zero in the parent container to remove the inter-column spaces added because of the display: inline-block and having to reset them, I simply added
.row.row-align-bottom > div {_x000D_
float: none;_x000D_
display: inline-block;_x000D_
vertical-align: bottom;_x000D_
margin-right: -0.25em;_x000D_
}
_x000D_
to the column divs to compensate.