How do I get over guilt?

(F14) So I said something really harsh to someone online even if it wasn't at all my intention. I wasn't being serious with what I said but it had been taken seriously. A few people told me that wasn't okay at all to say, even less if it did happen to be a joke.

I acknowledged that what I said was inherently violent, and I've apologized (though, I did get blocked by a few people after). It's just that I can't stop feeling guilty.

It's not like I know these people very personally and it would be very easy for me to just delete my account or something like that. But I just can't stop feeling guilty, whether I acknowledge it or ignore it.