JSFiddle - React, Tailwind, and code Playground

HTML

<button class="toggle">
  toggle
</button>
<div id="nav" class="hidden">
  element
</div>

CSS

.hidden {
  display: none;
}
div {
  margin-top: 10px;
}

JavaScript

document.addEventListener("DOMContentLoaded", function e() {
  var n = function(e) {
    document.getElementById("nav").classList.toggle("hidden")
  };
  document.removeEventListener("DOMContentLoaded", e);
  var t = Array.prototype.slice.call(document.querySelectorAll(".toggle"), 0);
  t.length && t.forEach(function(e) {
    e.addEventListener("click", n)
  })
})