Word-to-epub text colour

I do quite a lot of editing via Word to Epub, reading on an Android tablet using Pocketbook. I have a user colour setting of green text on black background. With some books, however, despite this the text is apparently black on black. In order to get the correct colour scheme, I have to select 'Ignore formatting' in Document Properties. Having the word document font colour as either Black or Automatic makes no difference. Does anybody have any suggestions, please?

Thanks
Colin