wp-admin css

Maybe I’m missing something, but is it possible to insert the following css with the free version of Code Snippets? The only custom code I need to run right now is to show the WPML language switcher in wp-admin on mobile, to manage multi-language comments, on my phone. Posting this css in Appearance > Customize doesn’t seem to work.

#wp-admin-bar-WPML_ALS {
	display: block!important;
}