[gnome-shell-sass] scrollbar color tweaks for dark/light

[Jakub Steiner <jimmac src gnome org>]

commit f0a0d1d3537912f41fef5aaa18b36cbd80b9b64f
Author: Jakub Steiner <jimmac gmail com>
Date:   Fri May 29 11:40:59 2015 +0200

    scrollbar color tweaks for dark/light
    
    - scrollbars were invisible in classic
    - sync color with gtk
    
    https://bugzilla.gnome.org/show_bug.cgi?id=750072

 _common.scss |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/_common.scss b/_common.scss
index 8469922..6b934eb 100644
--- a/_common.scss
+++ b/_common.scss
@@ -94,10 +94,10 @@ StScrollBar {
 
   StButton#vhandle, StButton#hhandle {
     border-radius: 8px;
-    background-color: $bg_color;
+    background-color: mix($fg_color, $bg_color, 60%);
     //border: 3px solid transparent; //would be nice to margin or at least to transparent
     margin: 3px;
-    &:hover { background-color: lighten($bg_color,10%); }
+    &:hover { background-color: mix($fg_color, $bg_color, 80%); }
     &:active { background-color: $selected_bg_color; }
   }
 }