JSFiddle - React, Tailwind, and code Playground

HTML

<button>Add campaign</button>
<button onclick="addText(this)">Click me</button>

CSS

button {
  color: white;
  display:block;
  font-size: 1.8em;
  background: #ff0022;
  font-weight: bold;
}

JavaScript

function addText(button) {
	button.innerHTML = "Add campaign"
}