What Webnauts said first gets straight to the heart of the question.

In my opinion, I'm pretty sure that Google's algorithm takes into account the contrast difference between the text colour and the background colour.

If the difference is negligible, then you will be punished in your rankings. However, I would say that if you feel it's borderline, you'll probably be OK. They don't want to punish people like you who are simply doing this on a design basis, rather than to hide keyword-rich text on their pages!

Have you got a link to the page in question? It would be useful to see it in context.

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