Live Demo not working on latest Chrome browser on macOS Monterey 12.6

[SouvikDcoder]

I am trying to use the Live Demo feature on the Phantom Jekyll theme, however, upon clicking the button, I am unable to get the full view of the Page, instead, I am getting a text-only page where I can see the below errors in the browser console.

Mixed Content: The page at 'https://jamigibbs.github.io/phantom/' was loaded over HTTPS, but requested an insecure favicon 'http://jamigibbs.github.io/phantom//img/favicon.png'. This request has been blocked; the content must be served over HTTPS.

You can find a copy of the screenshot here.

[SouvikDcoder]

Adding the screenshot here for quick reference.

[Muaath5]

Same on Firefox Mobile Android

It seems that CSS is not loading