On my website I'm using ja_atoms on J4.
I have defined different js and css as assets in template style section.
Those assets are loaded in every page except "MY ACCOUNT" one, that is the one used to access personal account informations, register a new user and so on.
Assets not loaded
for example templates/ja_atoms/css/marcom.css
Hi,
If it's CSS code, I recommend to put into the file: /templates/ja_atoms/css/custom.css
It will be safe when you update new version of template 
Dear saguaros Thank you very much for your reply.
At the very beginning I was using CUSTOM.CSS to add my styles. However when I've enabled HTTP Header plugin in Joomla to add "nonce" to js and css, this file does not receive nonce field from server.
If I use "assets" section those files receive correctly nonce field.