How to add CSS to WordPress

These are some helpful threads on wordpress.org:

https://wordpress.org/support/topic/hovering-settings/

https://wordpress.org/support/theme/twentytwentythree/

You can use the hidden customizer option to add your CSS. Append customize.php to your site admin URL.
E.g. https://example.com/wp-admin/customize.php

And add your custom CSS in the Additional CSS section and this should do the trick.
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