diff --git a/themes/pmahomme/css/theme_right.css.php b/themes/pmahomme/css/theme_right.css.php
index 67309328b..cb5f3d802 100644
--- a/themes/pmahomme/css/theme_right.css.php
+++ b/themes/pmahomme/css/theme_right.css.php
@@ -305,6 +305,13 @@ fieldset.tblFooters {
     border-radius: 0 0 4px 5px;
 }
 
+div.null_div {
+    height: 20px;
+    text-align: center;
+    font-style:normal;
+    min-width:50px;
+}
+
 fieldset .formelement {
     float:              <?php echo $left; ?>;
     margin-<?php echo $right; ?>:       0.5em;
@@ -381,6 +388,14 @@ th.condition {
     border: 1px solid <?php echo $GLOBALS['cfg']['BrowseMarkerBackground']; ?>;
 }
 
+/**
+ * cells with the value NULL
+ */
+td.null {
+    font-style: italic;
+    text-align: <?php echo $right; ?>;
+}
+
 table .value {
     text-align:         <?php echo $right; ?>;
     white-space:        normal;