CSSC (CSS constants) is a filter program, primarily for the Apache 2 web server, which implements immutable variables ("constants") in cascading style sheets (CSS). It's largely a re-implementation of Shaun Inman's CSS-SSC PHP script, only it's written in Python, operates as a server-side filter and is rather configurable. It also supports arbitrary recursion in constants definitions.
It is, however, just an implementation of a constants syntax, which to my mind should be in CSS anyway. If you want full programmatic features in your CSS, you should probably use Apache to make .css files be interpreted by e.g. PHP or Python instead.
-ssc-constant(linkColor)CSSC is available under the terms of the GNU General Public License
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