Quadra uses 2 captcha systems such as exclusive math captcha and Google reCAPTCHA.

Optionally these captcha systems or only validation can be used. Both can be used by copying from templates without editing. For Google reCaptcha, how it is used and the site key address are explained. This system is very effective against bots and spam mails. You can also easily use dark and light themes.

Math captcha is a more elegant look and a captcha system compatible with other inputs. You can use it directly without any adjustment. Each page visit, this system randomly and different asks the math question via the placeholder.

You can add error and success messages for each form on your page. You can edit this from the "data-submit-message" and "data-error-message" attributes of the form tag.

You can also add and remove rules for validation settings from the script file as desired. This validation system was created with jquery validation. You can visit plugin page from here and get much more informations about rules and using.