Inject own css into external page via proxy

[dev4q1]

Hi,

I was wondering if it would be possible with browsersync to inject my own css (html or file) into an external website (which I do not host) via the proxy option?

My scenario is that I have to style a lot of html content on an external page which I don't have access to the ftp. So I can't upload my css file or have it referenced in the .

For chrome there are some extensions where I can copy&paste my css into it but it's not very efficient.

Thanks for your help!

Quan