JSFiddle - React, Tailwind, and code Playground

HTML

<h2 class="createaccount-join">Enter the new account's information below. (font stack)</h2>
<p>Your browser + O.S. will use its notion of a matching font for one of the font names in the stack. Your browser's element inspector may tell you what it is. Here are the font names in the font stack, in order:</p>
<h2 style="font-family: 'Helvetica Neue'">Enter the new account's information below. (Helvetica Neue)</h2>
<h2 style="font-family: Helvetica">Enter the new account's information below. (Helvetica)</h2>
<h2 style="font-family: 'Nimbus Sans L'">Enter the new account's information below. (Nimbus Sans L)</h2>
<h2 class="bold-join" style="font-family: Arial">Enter the new account's information below. (Arial)</h2>
<h2 style="font-family: 'Liberation Sans'">Enter the new account's information below. (Liberation Sans)</h2>
<h2 style="font-family: sans-serif">Enter the new account's information below. (sans-serif, not a font name)</h2>
<h2 style="font-family: 'Made up font name'">Enter the new account's information below. ("Made up font name")</h2>
<p>And an all freely-licensed font stack:</p>
<h2 class="createaccount-join">Enter the new account's information below. (all-free font stack)</h2>

CSS

.createaccount-join {
    font-family: "Helvetica Neue", "Helvetica", "Nimbus Sans L", "Arial", "Liberation Sans", sans-serif;
}
.all-free {
    font-family: "Nimbus Sans L", "Liberation Sans", sans-serif;
}