Hi there!
Thanks for contacting us.
You may use the following code in your custom CSS:
.sppb-addon-optin-forms .sppb-optin-form .button-wrap .sppb-btn {
width: 100px;
line-height: 1px;
background: #dfc5c5;
color: #252525;
padding: 0;
}
You can change the color codes as per your need in the above snippet.
Note: Path towards custom CSS(Joomla 3): Extensions>Templates>Styles> Click on your current default template name then choose Template Options. Then find custom CSS within the custom code.
For translate the messages:
Please go to: \language\en-GB\en-GB.com_sppagebuilder.ini
And find out "Name", "Email" , and the line: "Your subscription to our list has been confirmed. Thank you for subscribing!" And change them with your desired text. https://prnt.sc/z0awov
Hope this helps!
Best Regards