Cannot Style a WP Forms Button

Please see  web page truenasreseller.com/truenas/. Using wordpress with a Divi theme and WPForms Basic license.

The form on the right has a next button that I have been trying to style. I have tried adding this to the general theme's CSS:

div.wpforms-container-full .wpforms-form button .wpforms-page-next {
background: #2193d1;
border-width: 0px!important;
font-family: 'Open Sans',Helvetica,Arial,Lucida,sans-serif;
color: #fff!important;
}

I also have this already in the CSS, and it's working on the submit button:
/*** change color of wp-forms button***/
div.wpforms-container-full .wpforms-form input[type=submit],
div.wpforms-container-full .wpforms-form button[type=submit] {
    background-color: #00aeef; /* Blue background */
    border: 1px solid #04a3df; /* Dark blue border */
    color: #fff; /* Text color */
    font-size: 1em; /* Size of text */
    padding: 10px 15px; /* Distance between text and border */
}

Within WP Forms, when I click on that button, it's got an option to add CSS classes. I tried adding et_pb_button  et_pb_button_2 et_pb_module et_pb_bg_layout_dark, which is the class of the other blue buttons on the page.  Also not working.

Can you help? Thanks!