[gnome-panel] theme: darken is not valid css

[Alberts Muktupāvels <muktupavels src gnome org>]

commit d6ef6cacca505fbb1f006b122bfb6accf7789d76
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Mar 17 21:13:14 2016 +0200

    theme: darken is not valid css

 data/theme/Adwaita/gnome-panel-dark.css |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/data/theme/Adwaita/gnome-panel-dark.css b/data/theme/Adwaita/gnome-panel-dark.css
index 4bc7219..cb7c14c 100644
--- a/data/theme/Adwaita/gnome-panel-dark.css
+++ b/data/theme/Adwaita/gnome-panel-dark.css
@@ -19,7 +19,7 @@ panel-applet > menubar menu {
 
 .gnome-panel-menu-bar menuitem:hover,
 panel-applet > menubar menuitem:hover {
-  background-color: darken(#4a90d9, 20%);
+  background-color: #215d9c;
   color: #ffffff;
 }
 
@@ -33,7 +33,7 @@ panel-applet > menubar menuitem:hover {
 }
 
 wnck-pager:selected {
-  background-color: darken(#4a90d9, 20%);
+  background-color: #215d9c;
 }
 
 na-tray-applet {