<article class="wrapper">
  <p class="my-element">If the browser supports the clamp property, this text will be sized fluidly as you resize the page. If not, the browser will ignore the clamp value because it doesn’t understand it.</p>
</article>

.my-element {
	font-size: 1.5rem;
	font-size: clamp(1.5rem, calc(1rem + 3vw), 2rem);
}