Last-child on ion-radio generated lists of items

Ion-radio seems to create many singly scoped items (rather than one list) (but its visible to the user as a single list)

This is fine however as a result its impossible to use css last-child to add a style to the last entry in the list (e.g. to curve the bottom left, bottom right corners)

In Safari / IOS this can be worked around by rounding a parent container element … but that doesn’t work on Android browser (4.2)

Anyone got a clever way to round bottom left / bottom right of an ion-radio created list of items?