Vertical Menus instead of, (or in addition to) Horizontal Menus

First, I’m working on Localhost and have no link to show you. I’m working on a bone stock layout of enfold feeling my way around your template.

I want to be able to put a vertical menu list on specific pages. The same design as the top menu for a consistent look to the theme, but instead of it displaying horizontal (display: inline), I want it to have all the main LI’s stacked vertically on top of each other and the sub menu LI’s sliding out horizontally by adjusting top/left positioning. This would be useful for footer blocks and sidebars. I can make my own custom menu in word press and use your CSS styling. I just want it to look the same and not basic text links that are bland and boring.

I am capable of understanding, hacking, duplicating your code for my own custom menu, but I’m striking out looking for display: inline CSS properties on the backend for NAV.main_menu UL Is this perhaps in a PHP menu template somewhere and not in the CSS?

Q1. Can you point me in the right direction to all of the CSS code blocks that impact this decision.
Or, if there is an easy way to accomplish a vertically oriented menu in your template, please let me know where to sniff around.
You have some of the styling already configured for a mobile environment.

Thanks for any input you can offer.

P.S. Edit to note above: I am also capable of dealing with PHP if this involves some coding in a template.