Hey Dennis
Yes, that code should work. I don’t see that code added in your custom CSS though. Did you add the code in Appearance > Customize > Additional CSS? It’s possible that you have syntax error in your before that code so WordPress won’t accept the code nor allow saving. Please check all your CSS in http://csslint.net/

That goes the same if you’ve inserted the code in X > Theme Options > CSS. The Global CSS is more forgiving but you need to watch out for syntax errors too.


If there are no syntax errors in your CSS code, it could be a saving issue which usually is caused by low memory. Sometimes, you can’t see the result immediately because of aggressive caching. Please also try:
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If you’re using a caching plugin, clear all caches including browser cache then deactivate your caching plugin and other optimization plugins.
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If you’re using a CDN, please clear the CDN’s cache and disable optimization services.
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Contact your host to increase your allocated memory or do it yourself by adding this code in your wp-config.php
define( 'WP_MEMORY_LIMIT', '256M' );
define( 'WP_MAX_MEMORY_LIMIT', '512M' );
Thanks.