.link {
  color: var(--link);
  background-image: linear-gradient(var(--link-underline), var(--link-underline));
  background-position: 0% 100%;
  background-repeat: no-repeat;
  background-size: 0% var(--link-underline-size);
  padding-bottom: 0.2rem;

  /* background-size is for hover animation, color & border are for theme fading: */
  transition: background-size 0.25s ease-in-out, color 0.25s ease, border 0.25s ease;
}

.link:hover {
  background-size: 100% var(--link-underline-size);
}