I have changed the color for all radio buttons incidence in the style sheet like this:
form.SSFKundeportal_Basic input.formRadioField_Standard {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic .radioValidState input, form.SSFKundeportal_Basic input.radioValidState {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic input.radioRequiredState, form.SSFKundeportal_Basic .radioRequiredState input,
form.SSFKundeportal_Basic input.radioInvalidState, form.SSFKundeportal_Basic .radioInvalidState input {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic .radioFocusState input, form.SSFKundeportal_Basic input.radioFocusState {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic span.radioFieldGroup_Wide {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic span.radioFieldGroup_OneColumn {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic span.radioGroup_Narrow {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic span.radioGroup_Wide {
color:#336699;
background-color:#FFFFFF;
}
form.SSFKundeportal_Basic span.radioGroup_OneColumn {
color:#336699;
background-color:#FFFFFF;
}