Proposal: @property(value) Selector

In the future (CSS3 possibly), there should be a new type of selector added:
the @property(value) selector. This selector would select everything where
the value of "property" equals the value of "value". For example,

@font-weight(bold) {
letter-spacing:-1px;
}

would select everywhere the 'font-weight' was specified to 'bold' and change
the 'letter-spacing' to '-1px'.

Of course, the rule could still be overridden by specifying a value for
'letter-spacing' in another, more specific selector just like all other
rules.