1
general::
No resentment or anger, as in I hope there are no hard feelings about excluding your group. This idiom uses hard in the sense of "severe" or "harsh," a usage dating from about A.D. 1000.
American Heritage Idioms
2
general::
Phrase(s): no hard feelings [and] not any hard feelings
Fig. no anger or resentment. • I hope you don’t have any hard feelings. • No, I have no hard feelings.
McGrawhill's American Idioms And Phrasal Verbs