diff --git a/less/mixins.less b/less/mixins.less
index 989ac0d706..7fcd14c8e4 100644
--- a/less/mixins.less
+++ b/less/mixins.less
@@ -183,10 +183,7 @@
     .box-shadow(inset 0 1px 1px rgba(0,0,0,.075)); // Redeclare so transitions work
     &:focus {
       border-color: darken(@borderColor, 10%);
-      // Write out in full since the lighten() function isn't easily escaped
-      -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.075), 0 0 6px lighten(@borderColor, 20%);
-         -moz-box-shadow: inset 0 1px 1px rgba(0,0,0,.075), 0 0 6px lighten(@borderColor, 20%);
-              box-shadow: inset 0 1px 1px rgba(0,0,0,.075), 0 0 6px lighten(@borderColor, 20%);
+      .box-shadow(inset 0 1px 1px rgba(0,0,0,.075), 0 0 6px lighten(@borderColor, 20%));
     }
   }
   // Give a small background color for input-prepend/-append