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Re: Relative font sizes

From: Jim Byrne <j.byrne@gcal.ac.uk>
Date: Wed, 16 Apr 2003 12:23:30 +0100
To: W3c_Access <w3c-wai-ig@w3.org>
Message-ID: <BAC2FBC1.1B99E%j.byrne@gcal.ac.uk>

James ,

There is more chance - if you are not careful - of ending up with unreadably
small text if a size is set in the body selector - because of the issues of
inheritance. For example, if you set the body to .9em - and then set the
paragraph selector  to .9em, and then set anchor selector to .9em - the
resulting link in a paragraph will be 90% of 90% of 90% of the browser
default size; it could get difficult trying to figure out why your links are
so small. 

With a good understanding of all the issues this can be avoided. So it
depends on who is designing the page - and how aware they are of potential
problems; for that reason I think it is safer not to set a size in the body
selector.

I am less concerned with trying with trying to achieve total consistency of
look and layout across browsers and platforms -  it's practically impossible
to achieve - and trying to do it takes a lot of time and energy. I try to
avoid spending too much of my time in 'workaround world'.

Re: relative units
For me using em units - although they also have problems - is the best of
the bunch.

There are problems with most units of measurement - including using keywords
- see http://www.alistapart.com/stories/fear4/4.html for some discussion on
problems with keywords. However I do agree that keywords are a good idea -
and if the balance of problems/virtues moved towards keywords I would be
happy to start using them.

All the best,
Jim

on 4/15/03 9:41 PM, James Craig at work@cookiecrook.com wrote:

> Byrne Jim wrote:
>> It's a good idea not set any size in the body selector - leave that to the
>> users default size - and then set your relative sizes for headers,
>> paragraphs and so on.
> 
> I disagree. This is where almost all the cross-browser and
> cross-platform font display differences arise. Now I am not saying you
> should set the body font to a pixel size, but what's wrong with a
> scalable font size for the body?
> 
> If you set it with a keyword for example (xx-small though xx-large), you
> give those child elements a baseline. Keyword sizes are still scalable
> in all browsers that I know of, and therefore will be relative to the
> users default size.
> 
> Without that baseline, the "relative sizes" have no consistency across
> browsers. The CSS hacks outlined in the links I posted are a way to get
> font-sizes on the same system consistent. IE5 and Mozilla/NS7 for
> example, do font-sizes differently. IE6 does font-sizes differently
> based on the DTD existance and position (rendering mode). And that's
> just teh Windows platform.
> 
> James Craig
> 

 
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Received on Wednesday, 16 April 2003 07:23:39 GMT

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