JS toggleClass start

Toggle class name on click in JS

by Marc Chehab

HTML

<div id="banner-message" class="alt">
  <p>Hello World</p>
  <button onclick="change()">Change color</button>
</div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#banner-message {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  font-size: 25px;
  text-align: center;
  margin: 0 auto;
  width: 300px;
}

button {
  background: #0084ff;
  border: none;
  border-radius: 5px;
  padding: 8px 14px;
  font-size: 15px;
  color: #fff;
}

#banner-message.alt {
  background-color: blue;
  color: white;
}

.alt button {
  background: #ffffff;
  color: #000000;
}

JavaScript

function change() {
var elem = document.getElementById("banner-message");
elem.classList.toggle("alt");
}