Form to match website

If you're using the card forms layout you may enable the smart embed option so the form takes the same layout from your web page. 

You will find the option while getting the form's embed code: https://www.jotform.com/help/34-Adding-a-Form-to-a-Web-Page 

If your form was created using the old layout, it may be customized with some CSS code: https://www.jotform.com/help/75-Customize-Your-Form-Using-Custom-CSS-Codes 

I hope this helps.