JSFiddle - React, Tailwind, and code Playground

HTML

<span hidden>H</span>	
<span>V</span>

<span hidden>H</span>

<span>V</span>

CSS

body {
    font-family: monospace;
}

JavaScript

var elems = document.getElementsByTagName('span');

for (var i = 0; i < elems.length; i++) {
    elems[i].hidden = !elems[i].hidden;
}