diff --git a/wp-admin/css/colors-classic.css b/wp-admin/css/colors-classic.css
index 674badb33e..56e521deb7 100644
--- a/wp-admin/css/colors-classic.css
+++ b/wp-admin/css/colors-classic.css
@@ -107,13 +107,16 @@ ul.category-tabs li {
 
 div.tabs-panel,
 .wp-tab-panel,
-ul.category-tabs li.tabs,
 ul.add-menu-item-tabs li.tabs,
 .wp-tab-active {
 	border-color: #dfdfdf;
 	background-color: #fff;
 }
 
+ul.category-tabs li.tabs {
+	border-color: #dfdfdf #dfdfdf #fff;
+}
+
 ul.category-tabs li.tabs,
 ul.add-menu-item-tabs li.tabs,
 .wp-tab-active {
diff --git a/wp-admin/css/colors-fresh.css b/wp-admin/css/colors-fresh.css
index f863da0c06..61dd33fd23 100644
--- a/wp-admin/css/colors-fresh.css
+++ b/wp-admin/css/colors-fresh.css
@@ -104,13 +104,16 @@ ul.category-tabs li {
 
 div.tabs-panel,
 .wp-tab-panel,
-ul.category-tabs li.tabs,
 ul.add-menu-item-tabs li.tabs,
 .wp-tab-active {
 	border-color: #dfdfdf;
 	background-color: #fff;
 }
 
+ul.category-tabs li.tabs {
+	border-color: #dfdfdf #dfdfdf #fff;
+}
+
 ul.category-tabs li.tabs,
 ul.add-menu-item-tabs li.tabs,
 .wp-tab-active {
diff --git a/wp-admin/css/wp-admin.css b/wp-admin/css/wp-admin.css
index 1d40bec6cf..898df53357 100644
--- a/wp-admin/css/wp-admin.css
+++ b/wp-admin/css/wp-admin.css
@@ -3191,7 +3191,12 @@ ul.wp-tab-bar {
 	margin-top: 12px;
 }
 
-ul.category-tabs li,
+ul.category-tabs li {
+	border-style: solid;
+	border-width: 1px;
+	position: relative;
+}
+
 ul.add-menu-item-tabs li.tabs,
 .wp-tab-active {
 	border-style: solid solid none;