diff --git a/styles/bootstrap/application.css b/styles/bootstrap/application.css
index fcbd6ba52..d3a0df5be 100644
--- a/styles/bootstrap/application.css
+++ b/styles/bootstrap/application.css
@@ -2,6 +2,14 @@ body { /* Add top padding for full-width layout */
 	padding-top: 60px;
 }
 img.mimeicon {
+  -moz-border-bottom-colors: none;
+  -moz-border-image: none;
+  -moz-border-left-colors: none;
+  -moz-border-right-colors: none;
+  -moz-border-top-colors: none;
+  border-color: #CCCCCC #AAAAAA #999999 #CCCCCC;
+  border-style: solid;
+  border-width: 1px 2px 2px 1px;
 }
 
 .list-action a {