Okay everyone, I wonder whether you might be able to help me come up with an effective solution for this-

Situation: We send out third party emails on a regular basis and so receive HTML code from a lot of different companies. We also have two brands in our company and the header/footer of these need to be included. At the moment we are setting up two separate campaigns. Pasting the header table just below the <body> tag of the HTML third party companies provide, and the same with the footer, just above the closing body. That's all well and fine. However, it means the header and footer aren't responsive because of classes.

What we need: I'm looking for a way to have a dynamic header and a dynamic footer (this is done easily enough with RPL (Responsys Programming Language)). However, I would like the header and footer to be responsive. If I put <style> classes with a media query inside the body of an email how supported is that going to be? Will it overright existing <style> media queries in the head of the email too? Is there anything else anyone can suggest?

Example layout - will this work?:

<third party media query>
<our media query>
<our header>
<third party email content>
<our footer>