Form doesn’t display on the right side

Hello.
Please open this file https://new.gimbelsinternational.com/wp-content/plugins/booking/css/client.css

( you can check how to edit files in WordPress menu in this article https://wpbookingcalendar.com/faq/how-edit-file-in-wp-menu/ )

then add this code to the bottom of this file:

.wpbc_booking_form_structure.wpbc_form_right .wpbc_structure_form {
    max-width: 680px;
}

Please do not forget to clear the browser cache before testing these changes.?