diff --git a/calendar/templates/default/app.css b/calendar/templates/default/app.css
index 23c1195063..8f2a75429b 100644
--- a/calendar/templates/default/app.css
+++ b/calendar/templates/default/app.css
@@ -72,6 +72,10 @@
 #calendar-sidebox_cat_id ~ * {
 	vertical-align: top;
 	display: inline-block;
+	background-color: transparent;
+    background-image: url(../../../vendor/bower-asset/jquery-ui/themes/redmond/images/ui-icons_469bdd_256x240.png);
+    border: none;
+    box-shadow: none;
 }
 #calendar-sidebox_buttons tbody {
 	width: 100%;
diff --git a/calendar/templates/pixelegg/app.css b/calendar/templates/pixelegg/app.css
index 6670c22983..a189ff9699 100755
--- a/calendar/templates/pixelegg/app.css
+++ b/calendar/templates/pixelegg/app.css
@@ -82,6 +82,10 @@
 #calendar-sidebox_cat_id ~ * {
   vertical-align: top;
   display: inline-block;
+  background-color: transparent;
+  background-image: url(../../../vendor/bower-asset/jquery-ui/themes/redmond/images/ui-icons_469bdd_256x240.png);
+  border: none;
+  box-shadow: none;
 }
 #calendar-sidebox_buttons tbody {
   width: 100%;