How to make double lines border in CSS, each line in different color, without using background image?

Question

How to make a double line border in CSS, each line in a different color without using background-image?

For example like this:

Answer 1

I don't think there is a way to do this without an additional element.

There's outline, but it doesn't allow a outline-bottom rule: An outline can only be identical on all four sides.

The :after pseudo-class will allow the adding of text content only, no elements.

Here's how to do it with an additional hr.