diff --git a/scss/_variables.scss b/scss/_variables.scss
index 15f5d8153e..cd911ba3c7 100644
--- a/scss/_variables.scss
+++ b/scss/_variables.scss
@@ -545,7 +545,7 @@ $input-btn-font-family:       null !default;
 $input-btn-font-size:         $font-size-base !default;
 $input-btn-line-height:       $line-height-base !default;
 
-$input-btn-focus-width:         .25em !default;
+$input-btn-focus-width:         .25rem !default;
 $input-btn-focus-color-opacity: .25 !default;
 $input-btn-focus-color:         rgba($component-active-bg, $input-btn-focus-color-opacity) !default;
 $input-btn-focus-box-shadow:    0 0 0 $input-btn-focus-width $input-btn-focus-color !default;