Grid: Expanding/Collapsing Columns

It's possible to make a grid column expand or collapse. This is useful when you want a column to be as wide as possible.

Example #1

Col 1 has more content
Col 2 expands as widely as possible.
Col 3 
<div class="grid">
    <div class="grid-col grid-col--sm-shrink">
        [...]
    </div>
    <div class="grid-col grid-col--sm-expand">
        [...]
    </div>
    <div class="grid-col grid-col--sm-shrink">
        [...]
    </div>
</div>