On Kindle there is no way to do what you want, but you should not need it anyway. Books properly formatted for Kindle will support Enhanced Typesetting and one of that features of that is:
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Dynamic color contrast: We added dynamic color text contrast to ensure a threshold of contrast between text color and page background color. We maintain the text hue to preserve intended differentiation, but adjust the text lightness as needed for different reading modes such as night mode, sepia, or green.
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I don't know about Apple Books. Someone else will have to address that.