Highlight / Focus captcha input field with error text on error

I using version 3.0.3.0

I have enabled basic captcha.

Rest fields are getting red border with error message below input field.

e.g. firstname must be between 3 to 30 characters....

how to do this for basic captcha input field ?
e.g. Captcha Field is empty and Captcha code not matching etc.. below captcha input field ??

I can't really understand what you're asking?

I am not sure what exactly you want to change with the OpenCart captcha.

Please be aware that the idea of a captcha originally was to prevent spambots from doing fake account registrations or sending spam messages via the Contact Us page. However, most modern spambots easily overcome captchas, hence captchas won't offer much of a protection anymore. We recommend using tools like the SpamBot Buster which doesn't need a captcha at all.