[MlMt] CSS selector for mailbox list and message list?

[Mike Hucka]

I've read about the css styling approach and have been able to tweak the 
colors of the message body (using MmMessagesWebView/stylesheet.css), but 
I can't seem to find the right way to affect the mailbox list and the 
list of messages in a mailbox.

Can someone point me in the right direction?

I'm using the widescreen layout, in case that matters.

Best regards,
MH