diff --git a/gtk/theme/HighContrast/_common.scss b/gtk/theme/HighContrast/_common.scss
index 58a198407d..a89c789310 100644
--- a/gtk/theme/HighContrast/_common.scss
+++ b/gtk/theme/HighContrast/_common.scss
@@ -1073,31 +1073,33 @@ treeview.view {
         color: $selected_fg_color;
       }
     }
-    & :last-child.button,
-    &:last-child.button { //treeview-like derived widgets in Banshee and Evolution
+    & button:last-child,
+    & button:last-child:hover,
+    & button:last-child:backdrop { //treeview-like derived widgets in Banshee and Evolution
       border-right-style: none;
     }
   }
 }
 
 %column_header_button {
-  border-width: 0 1px 1px 0;
+  padding: 3px 6px;
+  border-style: none solid solid none;
   border-radius: 0;
+  border-width: 1;
   background-image: none;
-  border-color: $bg_color;
+  border-color: mix($backdrop_fg_color, $backdrop_bg_color,50%);
   text-shadow: none;
   &:disabled {
-    border-width: 0 1px 1px 0;
     border-color: $bg_color;
     background-image: none;
   }
   &:backdrop {
-    border-color: $backdrop_bg_color;
-    border-width: 0 1px 1px 0;
+    border-color: mix($backdrop_fg_color, $backdrop_bg_color,50%);
+    border-style: none solid solid none;
     color: mix($backdrop_fg_color, $backdrop_bg_color,50%);
     background-image: none;
+    background-color: $backdrop_base_color;
     &:disabled {
-      border-width: 0 1px 1px 0;
       border-color: $backdrop_bg_color;
       background-image: none;
     }
diff --git a/gtk/theme/HighContrast/gtk.css b/gtk/theme/HighContrast/gtk.css
index 531421bc5c..d8cb08eb3e 100644
--- a/gtk/theme/HighContrast/gtk.css
+++ b/gtk/theme/HighContrast/gtk.css
@@ -1225,26 +1225,27 @@ treeview.view {
       box-shadow: none; }
     treeview.view header button:active {
       color: #fff; }
-  treeview.view header :last-child.button, treeview.view header:last-child.button {
+  treeview.view header button:last-child, treeview.view header button:last-child:hover, treeview.view header button:last-child:backdrop {
     border-right-style: none; }
 
 treeview.view header button, treeview.view header button:hover, treeview.view header button:active {
-  border-width: 0 1px 1px 0;
+  padding: 3px 6px;
+  border-style: none solid solid none;
   border-radius: 0;
+  border-width: 1;
   background-image: none;
-  border-color: #fff;
+  border-color: gray;
   text-shadow: none; }
   treeview.view header button:disabled {
-    border-width: 0 1px 1px 0;
     border-color: #fff;
     background-image: none; }
   treeview.view header button:backdrop {
-    border-color: #fff;
-    border-width: 0 1px 1px 0;
+    border-color: gray;
+    border-style: none solid solid none;
     color: gray;
-    background-image: none; }
+    background-image: none;
+    background-color: #fff; }
     treeview.view header button:backdrop:disabled {
-      border-width: 0 1px 1px 0;
       border-color: #fff;
       background-image: none; }