diff --git a/IPython/html/static/tree/less/tree.less b/IPython/html/static/tree/less/tree.less
index 9a12bde..ad10a93 100644
--- a/IPython/html/static/tree/less/tree.less
+++ b/IPython/html/static/tree/less/tree.less
@@ -179,3 +179,34 @@ ul#new-menu {
 #tab_content {
     padding-top: @page-header-padding;
 }
+
+#running {
+    .panel-group{
+        .panel {
+            margin-top: 15px;
+
+            .panel-heading {
+                background-color: #eee; /* @page-backdrop-color */
+                padding-top: 4px;
+                padding-bottom: 4px;
+                padding-left: 7px;
+                padding-right: 7px;
+            }
+
+            .panel-body {
+                padding: 0px;
+
+                .list_container {
+                    margin-top: 0px;
+                    margin-bottom: 0px;
+                    border: 0px;
+                    border-radius: 0px;
+
+                    .list_item {
+                        border-bottom: 1px solid #ddd;
+                    }
+                }
+            }
+        }
+    }
+}