Lets face it anyway, for anything perfectly flexible and scalable with xhtml/css, the whole design process will need to be wrapped in abstraction to iron out the bugs – and html/css will always be that way until browser renderings work all the same way – which is never because we will always have to support legacy.

CSS Variables allow authors to define variables that are reusable as property values anywhere in a stylesheet and queryable/modifiable through an extension of the CSS Object Model described in this document.

Er, I meant “now,” not “not.” Wish I could edit my posts. :-)

I hear you. The next version of AIR will include a much newer version of WebKit.

Whatever that means and whenever that is! :)
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“For that matter, how does AIR deal with apps that require a newer engine? Do you get a “your air is stale” message?”
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That’s a really good question. I imagine AIR has an update mechanism, but I have no idea how usable it is.

Not quite yet, though, if it’s only in the nightlies.

How often, I wonder, will Adobe update the webkit in AIR?

For that matter, how does AIR deal with apps that require a newer engine? Do you get a “your air is stale” message?

#toolbar LI {
background-color: red;
}
#sidebar LI {
border: solid 1px red;
}

But this means copy/pasting the selectors in multiple places, which makes these rules a bit brittle. It’d be nice to have an “@templates” directive or something like that to support this. E.g.

@templates {
buttonGeometry: {width:80px; margin:4px}
buttonTypography: {font-size:12pt; font-weight:bold}
}
#toolbar LI {
template: buttonGeometry, buttonTypography;
background-color: red;
}
#sidebar LI {
template: buttonGeometry, buttonTypography;
border: solid 1px red;
}


I still think it’s wrong to call them variables instead of constants, unless browsers implement this by allowing the variables to be dynamically updated from javascript.

@gordon: yes, it’s necessary. omfg, is it necessary! Without this, developers and designers for a product must agree on a process for documenting design changes (colors, spacing, font sizes) and making sure they are applied to the appropriate stylesheets. This is a non-trivial problem and the reality is that very few teams, if any, get it right. Web sites are constantly having design bugs introduced because of this, _and_ as the CSS grows more complex it becomes correspondingly harder to maintain.

Allowing developers and designers to express the critical elements of a design as variables that can be updated in a single place is a *huge* win!