Earnware Connect forms are styled with basic styles that can be overwritten.
How to load the default styles?
Go to Earnware Connect plugin dashboard, find Load Earnware Styles and click Checked to Load.
How to override default form colors?
Here is an example of how to change form button colors and input border to color red:
/*Earnware Connect button color*/
.sub-form-body .sub-form-field-radio.input-submit input[type=radio] + label,
.sub-form-body .sub-form-field-subscribe input
{background: red;}
/*Earnware Connect form border color*/
.sub-form-body .sub-form-field-email input
{border:1px solid red;}