diff --git a/phpBB/styles/prosilver/theme/cp.css b/phpBB/styles/prosilver/theme/cp.css
index 1e0edc616f..b574b0ae1f 100644
--- a/phpBB/styles/prosilver/theme/cp.css
+++ b/phpBB/styles/prosilver/theme/cp.css
@@ -393,13 +393,11 @@ ol.def-rules li {
 
 /* PM marking colours */
 .pmlist li.bg1 {
-	border: solid 3px transparent;
-	border-width: 0 3px;
+	padding: 0 3px;
 }
 
 .pmlist li.bg2 {
-	border: solid 3px transparent;
-	border-width: 0 3px;
+	padding: 0 3px;
 }
 
 .pmlist li.pm_message_reported_colour, .pm_message_reported_colour {
@@ -408,21 +406,25 @@ ol.def-rules li {
 }
 
 .pmlist li.pm_marked_colour, .pm_marked_colour {
+	padding: 0;
 	border: solid 3px #ffffff;
 	border-width: 0 3px;
 }
 
 .pmlist li.pm_replied_colour, .pm_replied_colour {
+	padding: 0;
 	border: solid 3px #c2c2c2;
-	border-width: 0 3px;	
+	border-width: 0 3px;
 }
 
 .pmlist li.pm_friend_colour, .pm_friend_colour {
+	padding: 0;
 	border: solid 3px #bdbdbd;
 	border-width: 0 3px;
 }
 
 .pmlist li.pm_foe_colour, .pm_foe_colour {
+	padding: 0;
 	border: solid 3px #000000;
 	border-width: 0 3px;
 }