Yes they are. That's what comes of doing things at 11pm.
It was when I was creating a video to show what I was seeing and talking my way through it that the issue became obvious to me - it was the fact that I had already visited the site and therefore the colour showing was the 'visited' one that the light suddenly dawned on me. So, I checked using a different browser and the colour became the 'default'. So, to fix it, I made 'visited' the same foreground and background as 'default' and everything worked. I can now move forward.