Responsive Borders

We've added the ability for Bootstrap's border utilities to respond to breakpoints. You can either add a border at a specific breakpoint, or remove an existing border at a breakpoint.

To add a border at a specific breakpoint, use class .border-{x}-{y} where x equals the breakpoint size hook (e.g. md) and y equals the border side (e.g. top). If a side is not provided, the border will occur on all sides.

In the following example, a blue border is added to the top side only, at the medium (md) breakpoint.

In the next example, a blue border is present on all sides, and removed at the large (lg) breakpoint.

The Sass for responsive borders is found in _e-supplementary-classes.scss under C. Responsive borders.