JSFiddle - React, Tailwind, and code Playground

HTML

<p>
ein text, hier der <a href="#">Link</a>.
</p>

CSS

p a{
  color: black;
	text-decoration: underline;
	text-decoration-thickness: 0.2rem;
}
p a:focus{
	color: black;
	text-decoration: underline;
	text-decoration-thickness: 0.2rem;
}
p a:hover, p a:active{
	color: black;
	text-decoration: underline;
	text-decoration-color: red;
	text-decoration-thickness: 0.2rem;
  transition: text-decoration-thickness 0.3s ease-in-out;
}