The Captcha component is based on popular reCaptcha api and integrated as a JSF Validator.
The theme does not follow the PrimeAgile theme, but has four different options: Red, White, Blackglass, and Clean.
|'red' (default theme)||'white'|
To implement the captcha and choose a theme, all you need to do is create a captcha object, and in the object page select the theme from the "Theme" dropdown and click save.
The captcha is usually used to verify a log-in or form submission, so are usually placed at the bottom of a form. There is a required option which makes it so when the user submits the form, it will only go through if the correct text is entered into the captcha.