Improved security of {muscle,pcsclite,ccid}.apdu.fr websites

I recently discovered the Mozilla Observatory service:

The Mozilla HTTP Observatory is a set of tools to analyze your website and inform you if you are utilizing the many available methods to secure it.

Before

Initially the 3 websites https://muscle.apdu.fr/, https://ccid.apdu.fr/ and https://pcsclite.apdu.fr/ I manage had a very bad score of F or 20/100.

F is is worst score. So I needed to do something to improve the situation and the security a bit.

After

After some configuration of the web server and some minor update of the web pages I now get a score of A+ or 110/100.

If you find something broken on the web sites please tell me. I may have missed something.

Conclusion

I think I could still improve the security. If you have ideas of what to do just tell me.