JSFiddle - React, Tailwind, and code Playground

HTML

<span>Testing 1.. 2.. 3..</span>
<div><p>Testing 1.. 2.. 3..</p></div>

CSS

body {
    font-size:20px;
}
span {
    font-size:3em;
}
div {
    font-size:2em;
}
p {
    font-size:3em
}