Re: font sizes in ems

Steve Knoblock wrote:
> I don't understand what is complicated about this idea. One em is the
> point-size of the type. Possibly, they confuse em with one point.

This has been an enlightening thread, but I'm still not sure I
understand some of the questions.

> Generally, I've tried to use percent for my margins because I want
them to
> be scalable. But I've know all along I wanted to specify them in em

You might want to declare an absolute minimum margin and augment it
with a margin specified in ems.
> David, you've helped clarify the terminology as it relates to CSS for
> Thanks to you and others here.

Go ahead, make my day. I sometimes feel I'm whistling in the wind and
sometimes wish I had been.

> This talk of ems and the example pages
> inspired me to add to a small test page of percent values. I had not
> thought of combining percent and em on one page to compare them. The
> is at http://home.att.net/~knoblock/css/EM_TypeSheet.html with links
to the
> other pages. I've added David's and Hakons's definitions of an Em. I
> appreciate any suggestions or corrections.

I wonder... do the separate em value and percent value pages add any
information not contained in the 'comparing' page? I couldn't see it.

Also, on first two pages you've used numerals for you IDs. NSN4 for Win
doesn't accept numerals for ID or CLASS, and so the sizes are all the

> Next, on to em margins.

Your example prompted me to try a demonstration page with em margins:


What I'd expected to take a few minutes took hours, as I tried to deal
with NSN's shortcomings. In NSN4.01, contrary to the CSS1 spec, em and
percent measures do not refer to the font size of the element itself
when the font size of the element is specified in em or percent. Em and
percent measures apparently refer to the closest ancestor with an
absolute font-size declaration.

So, even scripting IE3.n out of styling, authors still have some
limitations on the use of em and percentage measurements for paragraph
indents. It's a problem for authors wanting to use a paragraph
font-size different from the reader's default.

David Perrell