On: CSS Variables published as First Public Working Draft

[Kilimanjaro]

Or even this:

    :vars {
        header-color: #06c;
        header-font: helvetica;
    }
    h1 { 
        font-family: $header-font;
        background-color: $header-color; 
    }

[wdewind → Kilimanjaro]

Yeah, the name spacing part is crucial because you can do

:root { var-color: #000; }

p { var-color: #666; }

* { color: var(color) }

[pbhjpbhj → Kilimanjaro]

@, : and $ are already well used though.