phpvms/resources/sass/now-ui/now-ui-kit/_social-buttons.scss

.btn-twitter{
    color: $social-twitter;

    &:hover,
    &:focus,
    &:active{
        color: $social-twitter-state-color;
    }
}

.btn-facebook{
    color: $social-facebook;

    &:hover,
    &:focus,
    &:active{
        color: $social-facebook-state-color;
    }
}

.btn-google{
    color: $social-google;

    &:hover,
    &:focus,
    &:active{
        color: $social-google-state-color;
    }
}

.btn-linkedin{
    color: $social-linkedin;

    &:hover,
    &:focus,
    &:active{
        color: $social-linkedin-state-color;
    }
}