Compass provides a mixin to produce a vendor-prefixed stack of properties for CSS Filters. The syntax follows the W3C specification described here at http://www.w3.org/TR/filter-effects/.

Let's use the drop-shadow filter to solve our prior issue. We'll remove the existing box-shadow mixin and instead apply a CSS drop-shadow filter with the Compass mixin:

@include filter(drop-shadow(#ccc 1px 1px 0px));

And here is the effect in the browser:

Compass will let you apply all CSS filters in this manner, essentially following the W3C syntax for the relevant filter.