Re: Some Views on CSS

Russell Steven Shawn O'Connor wrote (4:36 PM -0400 4/10/98):


[ S N I P ! ]


You have neatly articulated the reasons behind the Core Style Project [1].
I don't quite follow you on the absolute/relative dichotomy - it's very
handy to set an absolute value (such as a pixel count) on the root of the
render tree, and then spec all the children in relative terms - but the
rest of the dilemma is certainly familiar. As I see it, the requirements
for both cascadable style and readily extensible documents/sites lead
inexorably to the conclusion that stylesheets must be modular, with each
module having a fixed selector structure covering every element in the
target DTD, and each complete family of modules providing descriptors for
every CSS(1?) property.

" If you were paying attention you may have noticed something a little
" disturbing as a result of what I have said.  There is a fundamental problem
" with CSS.  You can't specify rules for all selectors as is required for
" absolute and relative modules.  I can specify a colour scheme for all the
" HTML elements, but I can't be sure that the default style sheet for a UA
" has some rule like ``TABLE DIV P EM I {color:  red}'' that I haven't
" overridden that may conflict with my style sheet.  Somehow the ability to
" delete previous rules for all selectors that define a property must be
" added to CSS, likely by adding use of some kind of new @ rule.  I don't
" know of a good solution.  I just see the problem.

Does CSS2's Universal Selector[2] do it?

It's true that any selectors other than elements, pseudoelements, and
pseudoclasses are problematic for cascading. That's why it's desirable to
establish a common class/id namespace for HTML, and to fold these selectors
into the pseudostandard modules.

As for UA defaults, I think it's fair to guess at this point that any UA
whose defaults were to depart so dramatically from the Mosaic defaults[3]
as you describe might qualify as a new media type, alongside projector,
grid, handheld, TV, etc. Whole new stylesheet ballgame, needing its own
modules to accommodate cascading. For the screen media type, "Mosaic won."

[1] http://style.verso.com/stylist.html
[2] http://www.w3.org/TR/PR-CSS2/selector.html#universal-selector
[3] http://www.verso.com/agitprop/corestyle/base.html ;



p.s.: Nifty trick for Core Style Project watchers who use IE4: go surf
somewhere (preferably to a structured document) and paste the following
into the address field:

javascript:void(document.createStyleSheet("http://style.verso.com/?body=1;head=1
;marg=1;affo=1;comp=4"))

Try twiddling the numeric values (1-4) on body=1, etc.


Todd Fahrner
mailto:fahrner@pobox.com
http://www.verso.com/agitprop/

The printed page transcends space and time. The printed page, the
infinitude of books, must be transcended. THE ELECTRO-LIBRARY.
	- El Lissitzky, 1923

Received on Friday, 10 April 1998 19:23:08 UTC