Ok Guenni007, I just tested the website and the result is a yellow B.
I have to fix Strict Transport Security and Content Security Policy (Missing Headers).
We’re going to fix it.

Last Friday, the site was hacked. Instead of the homepage, we had a redirect to a Clearfix page. Admin users logged in, and fake plugins appeared. We removed everything. The next day, all the site’s images were gone.
We downloaded the backup (site and database), deleted everything, and started over.
We added more security plugins.
We still don’t know what happened; it’s definitely not just Enfold, but it could also be Woocommerce, and especially Revolution Slider, which was removed in the new version.
Nothing like this has ever happened before!
In any case thank you so much for your advice: precious!