diff --git a/html/css/calendar-blue.css b/html/css/calendar-blue.css
index 85172b05e..bc809b59b 100644
--- a/html/css/calendar-blue.css
+++ b/html/css/calendar-blue.css
@@ -1,6 +1,6 @@
 /* The main calendar widget.  DIV containing a table. */
 
-div.calendar { position: relative; z-index:13; }
+div.calendar { position: relative; z-index:400; }
 
 .calendar, .calendar table {
   border: 1px solid #556;