diff --git a/extlink.css b/extlink.css
index 9082064..c4488d6 100644
--- a/extlink.css
+++ b/extlink.css
@@ -12,6 +12,12 @@ span.mailto {
   padding-right: 12px;
   text-decoration: none;
 }
+a.ext:after {
+  content: " - External link";
+  position: absolute;
+  left: -10000px;
+  top: auto;
+}
 
 /* Hide the extra spans when printing. */
 @media print {