To make your form responsive you need to provide responsive CSS styling to the relevant standard HTML form elements.
You may adjust the responsiveness of the form by using the @media rule
@media screen and (max-width: 950px) {
//your CSS here.
}
See Styling Contact Form for a general explanation of styling CF7 forms using CSS.
There is a link at the bottom of the page to a comprehensive and detailed article on Styling Contact Form 7 Forms. The article shows people, with suitable HTML & CSS skills, how to change the appearance of their Contact Form 7 Forms to meet their particular requirements.
