diff --git a/static/includes/_forms.scss b/static/includes/_forms.scss
index 59644ae7..06181ab5 100644
--- a/static/includes/_forms.scss
+++ b/static/includes/_forms.scss
@@ -101,7 +101,7 @@ $cancel-button-icon: '\f00d' !default; /* remove icon */
 			background: $widget-custom-radio-checkbox-marker-color;
 		}
 		&[disabled]:checked + span::after {
-			background: grayscale($widget-custom-radio-checkbox-marker-color);
+			filter: grayscale(100%);
 		}
 
 		&:focus + span {