JSFiddle - React, Tailwind, and code Playground

HTML

<form action="">

<!-- this is like the echo in php IS DISABLED -->
<input type='submit' name='buy' value='Buy' disabled='disabled' id='buy'/>
<!-- End of echo in PHP -->

</form>


<script>    
  var buyButton = document.getElementById('buy');
buyButton.disabled = false; // IS ENABLED
  </script>