diff --git a/sass/form/shared.sass b/sass/form/shared.sass
index 2f0de926..3005587e 100644
--- a/sass/form/shared.sass
+++ b/sass/form/shared.sass
@@ -11,12 +11,12 @@ $input-hover-border-color: $border-hover !default
 $input-focus-color: $text-strong !default
 $input-focus-border-color: $link !default
 $input-focus-box-shadow-size: 0 0 0 0.125em !default
-$input-focus-box-shadow-color: rgba($link, 0.25) !default
+$input-focus-box-shadow-color: bulmaRgba($link, 0.25) !default
 
 $input-disabled-color: $text-light !default
 $input-disabled-background-color: $background !default
 $input-disabled-border-color: $background !default
-$input-disabled-placeholder-color: rgba($input-disabled-color, 0.3) !default
+$input-disabled-placeholder-color: bulmaRgba($input-disabled-color, 0.3) !default
 
 $input-arrow: $link !default