In the module configuration, I'd recommend setting the Module Class Suffix to something like "-jfbclogin". Then, if you add the following to your template, it should fix the extra padding:
.module-jfbclogin {
padding: 0px;
}
Obviously, you can set the padding to whatever you want. Currently, it's 15px all around, just so you know.
Good luck, and let us know if that works for you!