P and CSS

It still kills me to compare the P language, that Grif and Amaya implement, and CSS2.... I had today to do a very simple thing: position the right side of an absolutely positioned box relatively to the left side of the document. In P, that very easy, something like

Right: Enclosing.Left + 150px;

In a CSS-based model, that's not directly possible and I have to query first the width of the document, remove the 150px from that length and then only set the 'right' property. I don't even mention the fact that CSS cannot do a substraction...

Yes, I know, it's feasible. But I find it largely suboptimal compared to P.

Vincent, Irène, that style language of yours was/is so nice.