diff --git a/libreplan-webapp/src/main/webapp/common/css/libreplan_zk.css b/libreplan-webapp/src/main/webapp/common/css/libreplan_zk.css
index ebde77841..3284891af 100644
--- a/libreplan-webapp/src/main/webapp/common/css/libreplan_zk.css
+++ b/libreplan-webapp/src/main/webapp/common/css/libreplan_zk.css
@@ -853,6 +853,9 @@ div.z-listbox-pgi-b {
     font-weight: bold;
     margin: 4px 3px 2px 0;
     padding: 1px 5px;
+    height: 14px;
+    font-size: 9px;
+    width: 5px;
 }