[MlMt] What is the difference between the different HTML stylings?

[Jan Erik Moström]

For the first time I looked at the HTML options ... and notice that 
there were different themes available. So I sent a couple of test mails 
to myself (to two different accounts) and checked how they looked in 
gmail (web and Apple Mail) and to another address (Mailmate and Apple 
Mail).

But they look the same. So either I'm missing something or I have turned 
on some option to not view HTML in my different clients but I can't 
figure out what.

Any ideas?

= jem