diff --git a/scss/_mixins.scss b/scss/_mixins.scss
index 8b0d4bf40a9..defb76a60bf 100644
--- a/scss/_mixins.scss
+++ b/scss/_mixins.scss
@@ -172,7 +172,10 @@
 // --------------------------------------------------
 
 @mixin placeholder($color: $input-color-placeholder) {
-  &:-moz-placeholder {
+  &:-moz-placeholder { /* Firefox 18- */
+    color: $color;
+  }
+  &::-moz-placeholder { /* Firefox 19+ */
     color: $color;
   }
   &:-ms-input-placeholder {