Hello morenavecchi,
If you edited the zass-responsive.css directly in the theme folder – that’s normal. Any file you modify must be copied in the child theme (keeping the same folder structure of course) and edited there. e.g. – for the zass-responsive.css you’d need to create a folder named “styles” under zass-child and copy the file there. After that, you can edit the files.
As for the translation, if done the right way it can’t be affected by an update. I’d suggest using a plugin like Loco Translate for any edits on text strings:
hope this helps.
Regards,
Dimitar
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