Live demo & code generator

<!-- Add the script and a container -->
<script src="https://cdn.captcha-cdn.net/captchala-loader.js"></script>
<div id="captchala-container"></div>
<script>
  loadCaptchala(function () {
    Captchala.init({
      appKey: 'YOUR_APP_KEY',
      product: 'float',
      lang: 'en',
      theme: { custom: { brightness: 'light' } }
    })
    .appendTo('#captchala-container')
    .onSuccess(function (res) {
      // Send res.token to your backend for server-side validation
      console.log('token:', res.token);
    });
  });
</script>