Inset image border

It's not as simple as it seems to make an inset image border. We need a container element as well as a pseudo element for it to work.

figure {
  position: relative;
  display: flex;
}

figure:before {
  content: '';
  border: 1rem solid red;
  width: 100%;
  height: 100%;
  position: absolute;
  box-sizing: border-box;
}