"I ran the current site through a colour blindness filter and it seemed to do OK. The three kinds of link could be distinguished through brightness levels. Of course, it may not be a perfect simulation - are you colourblind yourself? If so, what parts are hard to see?"
First of all, kudos for you for having used the filter! That's very thoughful.
No, I'm not colorblind but I work with someone who is and he has told me that it is hard to differenciate colored text on a black background. I have become sensitized to the issue after having to listen to some of our developers bitch about having to make "concessions for a few people". I wanted to wring their necks.
I have what might be considered the opposite problem, I cannot tell if colors "go together". My wife assures me that knowing what color goes with what is a normal human trait and that I am difficient in this regard. I think it is "nuture, not nature" and she just uses this to make me change clothes before we go out. I get even by wearing one blue and one black sock and waiting till we get home to tell her

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