diff --git a/src/wp-admin/css/colors/_admin.scss b/src/wp-admin/css/colors/_admin.scss
index da53b00840..928670d2b1 100644
--- a/src/wp-admin/css/colors/_admin.scss
+++ b/src/wp-admin/css/colors/_admin.scss
@@ -408,12 +408,7 @@ ul#adminmenu > li.current > a.current:after {
 }
 
 .media-selection .attachment.selection.details .thumbnail {
-	-webkit-box-shadow:
-		0px 0px 0px 1px #fff,
-		0px 0px 0px 3px $highlight-color;
-	box-shadow:
-		0px 0px 0px 1px #fff,
-		0px 0px 0px 3px $highlight-color;
+	box-shadow: 0 0 0 1px #fff, 0 0 0 3px $highlight-color;
 }