Ckeditor Remove Existing Font Color and Prevent in Future

[Sovereign Grace Singles]

Hi,

People have been using multiple font/text colors in posts. I would like to not allow other font colors. The problem is if I remove the option from Ckeditor it is still available when people paste colored font in as rich formatting.  Is there a way for all font colors not black to be turned black and to disable the future use of font/text colors in the future? I also do not want raw font code to display if it is posted as rich formatting in the editor. 

Thanks,
William

[Linguica]

[Sovereign Grace Singles]

16 minutes ago, Linguica said:

And how would I change the text which has already been previously modified. I have posts made with all kinds of colors by members. I'd like to change them back to black. Could this be done with CSS?

[Linguica]

...probably? I imagine you could add something like

.ipsComment .ipsComment_content .cPost_contentWrap {
  color: black !important;
}

or whatever CSS selector works.