Call it an early Christmas present...
I recently created the attached email template to use as part of a product launch, and did some fairly extensive testing between various email clients. This is my favorite template to use for mobile, so what the heck. Spreading a little nerdy joy this holiday season!
I stripped our images, text, and links out of this version, but everything already lives in a Marketo-editable section for you. All you should have to do is edit the color palette for your needs, save the template, and create emails. If you want to duplicate or remove sections, they're marked out pretty well with HTML comments.
To that end... here's some helpful hex codes for swapping out the colors (use find/replace in dreamweaver or whatever HTML editor you prefer).
Yellow Banner: #ffdb0a
Dark Gray background: #444444 (caution: some of the text is also this color, so find/replace all is not necessarily your friend here)
Section 2 Background: #f7f7f7
Section 3 Background: #dedede
Blue Buttons: #2faeff