JSFiddle - React, Tailwind, and code Playground

HTML

<div><p>Hello</p></div>

CSS

div {
    display:block;
    width: 200px;
    background-color:blue;
}
p {
    display:inline;
}

JavaScript

var dWidth = $("div").width();
var pWidth = $("p").width();
var starting = 1;
while (pWidth < dWidth) {
    $("p").css("font-size",starting+"em");
    pWidth = $("p").width();
    starting = starting + .1;
}