Today's style sheet standards: the great vision blinded

Our research into style sheet systems and languages (Proteus and PSL) shows that there are alternatives to CSS and XSL that more closely meet the necessary criteria. The PSL style language has a syntax especially designed for the style sheet task and has traditional computational features including mathematical expressions and conditionals. In contrast to XSL, PSL does not emphasize transformations, and it uses constraints, rather than flow, to specify layout. Furthermore, there are other style languages, such as the Thot structured document toolkit's P language and the more recent Constraint CSS. While we realize that substantial resources have been invested in CSS and XSL, we nevertheless urge the Web community to more fully explore alternate approaches to style sheets.