diff --git a/gtk-3.0/gtk-widgets.css b/gtk-3.0/gtk-widgets.css
index b98147b..1916cdd 100644
--- a/gtk-3.0/gtk-widgets.css
+++ b/gtk-3.0/gtk-widgets.css
@@ -242,6 +242,8 @@ button.flat {
       color: alpha(@theme_fg_color, 0.7);
       background-color: transparent; }
   button.flat:backdrop {
+    border-color: transparent;
+    background-color: transparent;
     color: @theme_unfocused_fg_color; }
 
 checkbutton.text-button, radiobutton.text-button {
@@ -1714,6 +1716,8 @@ toolbar {
         color: alpha(@toolbar_fg_color, 0.7);
         background-color: transparent; }
     toolbar button.flat:backdrop {
+      border-color: transparent;
+      background-color: transparent;
       color: @theme_unfocused_fg_color; }
   toolbar menubar {
     -GtkToolbar-button-relief: normal; }