Defining the width in Contact 7

I need to accurately determine the width of both text fields and text areas in Contact 7.

This script does a great job for setting the width of text areas:

.wpcf7 textarea { width: 400px; }

How do I determine the width of text fields?

For example, the Captcha field only needs room for five characters, but it is the full width of the page.

Thanks!

https://www.ads-software.com/plugins/contact-form-7/