Hello,
1) Add the following code to child theme style.css to change the styles of the FB button
.et-facebook-login-button {
background: #ffffff;
opacity: 1;
color: #3b5998;
border: 1px solid #3b5998;
}
.et-facebook-login-button:hover {
background: #3b5998;
color: #fff;
}
2. It’s not one-line solution to implement Google and Instagram loginization. Unfortunately, our basic support does not include additional customization services to implement new features. Submit customization request here if you want to implement these options.
Regards