Fix direct visibility style for light theme (#14727)

app/javascript/styles/mastodon-light/diff.scss

@@ -256,14 +256,6 @@ html {
   background: $ui-base-color;
 }
 
-.status.status-direct {
-  background: lighten($ui-base-color, 4%);
-}
-
-.focusable:focus .status.status-direct {
-  background: lighten($ui-base-color, 8%);
-}
-
 .detailed-status,
 .detailed-status__action-bar {
   background: $white;