JSFiddle - React, Tailwind, and code Playground

by j08691

HTML

<form name='form-main' onsubmit='return validate()' action='' method='post'>
    <input type='submit' id="sub"  value='I accept - Download the GM!' />
</form>

JavaScript

function validate() {
    // this is just to test if it actually shows
    document.getElementById('sub').disabled=true;
    alert('You must not leave any of the fields blank!');
    return false;
}