I've created several guided landing page templates for Marketo which work well. These templates use SCRIPT and STYLE tags in the HEAD and footer area to link to external css and scripts.
I converted a landing page template to an email editor 2.0 template and all seemed well, at first glance, Marketo shows me these templates as rendering fine. However when doing an actiual test send and checking in GMail, none of my styles render.
Is this because I am linking to external styles?
Where should my styles be placed and how complex can then be?
Is there a best practice rule for CSS in emails?
All the email templates I have looked at use tables and inline CSS, I am sure this is done for a reason, why, is this the way to go?