Why form's fields looks like different?

CF7 now uses the new HTML5 input[type=”email”] for email fields and input[type=”text”] for other fields.

Looks like the CSS in your current WordPress theme does not cater for this new HTML5 email input field.

https://contactform7.com/faq/#Why_does_my_email_address_input_field_look_different gives some guidance on how make these fields look the same in your current WordPress theme.

See Styling Contact Form for a general explanation of styling CF7 forms using CSS. If you are not familiar with CSS, this page also includes some links to where you can learn CSS.

Thank you! solved.