How to solve nginx reverse proxy mixed content(http, https)

issue

I have got that partially working. If I access via HTTP everything is fine except not encrypted, but if I access via HTTPS the web pages are broken and I got this kind of error: Mixed Content: The page at 'https://domain.com/service1' was loaded over HTTPS, but requested an insecure stylesheet 'http://domain.com/service1/blahblah.css'. This request has been blocked; the content must be served over HTTPS.

I also got this kind of warning: The page at 'https://domain.com/service1/' was loaded over HTTPS, but is submitting data to an insecure location at 'http://domain.com/service1/': this content should also be submitted over HTTPS.

fix

This worked for nginx https proxy >> nginx http serving Django backend

Inside a location directive:

proxy_set_header X-Forwarded-Proto $scheme;