JSFiddle - React, Tailwind, and code Playground

HTML

<input type="number" min="0.5" max="8" step="0.1" required id="volume" class="form-control" name="voilume">

<div id="button">FOO!</div>

CSS

input:valid~div#button {
  display: block;
}

input:invalid~div#button {
  display: none;
}