Translate admin panel login.

[maciejmodl497d]

Hello, can I translate the messages from the admin login panel with a csv file? I do not have a custom administrator theme yet. Can I translate messages, for example (screen), without a theme?
https://imgur.com/a/7uHuFC4

[maciejmodl497d]

Update. I was able to add a custom admin theme, I added the csv file to the i18n folder. Unfortunately, the translation does not work everywhere, does anyone know where I can translate this message (error message)?
https://imgur.com/a/CQHKf7v

[maciejmodl497d · Accepted solution]

Ok translations started working, I had to clean the translation cache three times with this command 

php bin/magento setup:static-content:deploy lang_LANG -f