The netlify site name is xaitoday.netlify.app
Custom domain is xai.today but I get a 404 from https://xaitoday.netlify.app as well and any site previews.
I followed the steps outlined here. The index.html file looks fine to me.
I recreated some rsponse headsers as requested.
Thanks for reaching out and welcome to Netlify’s Support Forums!
It appears that you’ve changed the DNS configuration for your apex domain and www subdomain.
For your apex domain, xai.today, please just keep the A Record that’s pointing to 75.2.60.5. The AAAA Record (IPv6) will cause an issue with your SSL certificate.
For the subdomain www.xai.today, you’ll want to configure a CNAME Record that points to xaitoday.netlify.app.
In regards to the Page not Found issue, I don’t see a build command declared. Could you review this doc:
You can add the build command in the UI here:
Additional information can be found here:
This site should help with deploying Hugo sites on Netlify.