I used to pull stunts like this all the time as soon as tables came. Really ugly, and may seriously embarrass any validator you run it trough: overlapping table cells. Works in most browsers though and even without css.

No, most css doesn't work in emails, stick to tables and images.

For now though, you're stuck with <table> and CSS2 support for your layouts.

I hate to be the guy who will destroy your day but... Tables. You need to work with nested tables/cells. If you think Gmail is annoying you will cry in agony if you also need Outlook support.Work with the good old HTML from the early 2000's. That's the only way to be sure everything will work as intended.Anything else will mostly result in a horrible mess, broken design and incompatible layouts.

I would try designing your mail-template as "normal" as possible. Tables help a lot for example (yuck).