Last month I posted a short rant entitled Unusual CSS Reference after noticing that a W3C page called Learning CSS reported CSS and HTML errors when I attempted to validate it. The page’s hover effects also looked better in IE6 than in Firefox and Opera.

This drew comment from W3C representative Bert Bos, who wrote to me. His message reads:

I’m sorry that you find the hover effect ugly. That’s a matter of opinion. But, I must protest against your claims that the page was designed only for IE6 and that the page is invalid.

In fact, the page was designed so that it looks the same in Konqueror, Safari, Firefox, Opera and related browsers. IE6 shows the style a bit degraded, because of bugs in IE6, but still readable. Whether it looks appealing is a matter of taste, but I think it looks OK.

The page also has both valid HTML and valid CSS.

The HTML validator validates the page correctly (“This Page is Valid”). A long-standing bug in the report generator makes it print “no Doctype found,” although the doctype is there, as you can see by looking at the source.

The CSS validator finds no errors in the style sheets, but it reports three errors in the LINK elements in the HTML source. Those elements are in fact correct. The error is in the CSS validator, which hasn’t yet been updated to implement the Media Queries specification.

I’ve never been in contact with the W3C before, so I was quite surprised to receive the message. Great to know that the W3C folks read the items posted at HTMLfixIT, and really pleasing that a representative would go to the trouble to respond! And since Bert wrote the book on CSS I can’t imagine a higher authority on the subject.

The hover effect is subtle in IE6 and very dominant in Firefox and Opera. As Bert states, it’s clearly a matter of opinion as to whether one looks ugly or not.

When I commented on the HTML validation errors, I based my assessment on the mark-up errors detected by Firefox’s HTML Validator Extension. This tool reports some warnings. However, as Bert states, the HTML does in fact validate using the official W3C Validator, with the bug Bert describes incorrectly flagging “no Doctype found.”

Last month when I attempted to validate the CSS I did so using the link from Firefox’s Web Developer Extension, which gives the 3 errors and 90 warnings I described. Bert reports that the style sheets themselves validate and do not contain errors, and since I see 24 CSS files linked from the page I’m more than happy to take his word on that.

So where does that leave us?

1. I was incorrect when I stated “The page appears to have been written to look appealing in IE6, and appalling in FF and Opera”. It wasn’t written to look that way after all.
2. There are no HTML errors on the page. Rather, the Firefox HTML Validator Extension gives a result which is not consistent with the W3C Validator, while the Validator’s report generator contains a long-standing bug which reports an error that does not exist.
3. There are no CSS errors on the page. Instead the Validator itself contains an error and has not yet been updated to implement the Media Queries specification.

There are no errors in the W3C’s pages. Instead, there are issues with the W3C’s validation tools.

This article was posted on Thursday, February 8th, 2007 at 3:01 pm