JSFiddle - React, Tailwind, and code Playground

HTML

<html>
    <body>
      <div id="output">0</div>
      <button id="increment">Increment</button>

      <script>
        var counter = 0;
        var output = document.getElementById('output');  
        document.getElementById('increment').onclick = function() {
          counter += 1;
          output.innerHTML = counter;
        };
      </script>
    </body>
  </html>