— A couple of readers take issue with my mini-rant on the design bug in Movable Type and Blogger where font-size is specified in pixels rather than in the handy font-size keywords (medium, small, and x-small) that work so well, pointing me to the Urban Legend that moved designers in this wrong direction (A List Apart: Fear of Style Sheets 4)
Who goofed? The W3C or the IE/Windows team? It doesn’t really matter. What matters is that the keywords don’t map to expected sizes, and an incompatibility exists not only between different manufacturers’ browsers, but between the Mac and Windows versions of the same browser.
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So what can you do? Sadly, until browser makers agree on the right way to render absolute font size keywords, all you can do is ignore the W3C recommendations and use pixels in your Style Sheet. Or do not use sizes at all.
With all due respect to the folks who run A List Apart, this is bullshit. IE 6 and Netscape 6 render fonts specified by keyword exactly the same way, and just as you would expect them to be rendered – medium is a normal size font, small is smaller than medium, and x-small is smaller than small. They also render “medium” at the same size as Netscape’s old font size “3”, for whatever that’s worth. And – and this is the big deal – if your visitor wants to see the font-size defined by keyword larger or smaller, he can do so simply by changing the Browser’s View->Text Size setting; if you defined it in pixels, this adjustment does nothing.
Now it may very well be the case that IE 3 or Netscape 4 didn’t render these keywords correctly; those browsers have so many problems with CSS that it really doesn’t matter. So the fact remains that a font defined in pixels won’t display as you envision on high-res displays, and there’s not a damn thing the user can do about it, while a font defined by keyword will display correctly in a modern browser, and the user has control over it in any case. If this is some sort of unique issue for Mac people, c’est la vie.