CSS Color management with SASS

$base-color:#ff0000;

DARKEN & LIGHTEN

darken( $base-color, 10% ) ;
lighten( $base-color, 10% );

SATURATE, & DESATURATE

saturate( $base-color, 20% ) ;
desaturate( $base-color, 20% );

ADJUST-HUE

adjust-hue( $base-color, 20% );

ADDING ALPHA TRANSPARENCY

rgba( $base-color, .7 );

TINT & SHADE

tint( $base-color, 10% );
shade( $base-color, 10% );

SOURCE
http://migre.me/cGbmY