Color and transparency (opacity, alpha value)

First I want to apologize if I'm not on the right list. Please, 
point me to a more appropriate if applicable.

I see the color module for the CSS3 spec is in its last call stage 
and I've wondered if this sounds considerable: I want to set a 
background color of an element using a keyword (a system color: 
Caption, ThreeDFace etc. or an attr(color) maybe) and I want this 
color with some fixed opacity value.

In the current spec the only way to specify semi opaque color is to 
specify it as whole:

RGBA or HSLA color values

Does it sound reasonable to have ability to set the color opacity as 
separate value? Something like this:

E {
   color: black alpha(0.5);

this way I could specify only color opacity for the color without 
changing the current color:

E {
   color: alpha(0.5);


Received on Sunday, 4 May 2003 17:01:04 UTC