My PC has white text on a black background, BUT both browsers are set to show the colours set by individual websites (so, for example, my own site http://www.macfh.co.uk/CEMH.html comes up in the correct colours of white on dark blue), but in common with many others sites, W3's self-edit examples, such as ahem this one Try It Yourself Color Example, comes up as white on white, most probably because the site's styling sets the background colour explicitly to white, but fails to set the foregorund colour, which, being on a machine with white text, also defaults to white.
Surely, the number one rule of setting colours is either to set both background and foreground, or else neither, never just one or the other.
This 'half-baked' phenomenon is so widespread that I've now created a demo page for it ...
http://www.macfh.co.uk/Test/ColourSchemesBugs.html
... although it refers to MS sites, W3's exmples are just as bad.
Please remove the constant annoyance from an otherwise excellent series of sites by fixing this.
