Only last set of box-shadow values being evaluated about closure-stylesheets HOT 1 CLOSED

@def FG_LIGHT rgb(255,255,255);
@def FG_MID rgb(128,128,128);
@def FG_DARK rgb(71,71,71);

@defmixin boxshadow(COL1,COL2,COL3) {
  box-shadow: inset 0px 0px 0px 1px COL1, inset 0px 2px 1px 0px COL2, inset 0px 0px 0px 2px COL3;
}

.foo {
  @mixin boxshadow(FG_DARK,FG_LIGHT,FG_MID);
}

.bar {
  box-shadow: inset 0px 0px 0px 1px FG_DARK, inset 0px 2px 1px 0px FG_LIGHT, inset 0px 0px 0px 2px FG_MID;
}

.foo, .bar {
  box-shadow: inset 0 0 0 1px #474747 , inset 0 2px 1px 0 #fff , inset 0 0 0 2px #808080;
}