Hi Christian - we don’t support the @font-face attribute natively, in that we don’t have a place for you to upload font files that aren’t already included in Unbounce.

You can still make it work though. You’ll need to upload the fonts to a different location. Then, because Firefox restricts cross-domain linking to fonts, you’ll need to allow access to the font you just uploaded with one of these methods: https://coderwall.com/p/v4uwyq