diff --git a/scroll_to_top.css b/scroll_to_top.css
index ae5dc4f..cb7047d 100644
--- a/scroll_to_top.css
+++ b/scroll_to_top.css
@@ -5,7 +5,7 @@ Back to top button
 	position: fixed;
 	bottom: 10px;
 	margin-left: 20px;
-	z-index:9999;
+	z-index:9990;
 	/*IE6 hack */
 		 _position: absolute;
 		 _top:expression(documentElement.scrollTop+body.scrollTop);