diff --git a/scss/_custom-forms.scss b/scss/_custom-forms.scss
index 4afc08087633..06725ff36445 100644
--- a/scss/_custom-forms.scss
+++ b/scss/_custom-forms.scss
@@ -390,7 +390,7 @@
   appearance: none;
 
   &:focus {
-    outline: none;
+    outline: 0;
 
     // Pseudo-elements must be split across multiple rulesets to have an effect.
     // No box-shadow() mixin for focus accessibility.