Second Level Drop Down Menu?

I’d really like to be able to add a second level drop down menu to the current website I’m working on, but the theme I’m using doesn’t have it as an option.

I have a feeling that I should be able to do this via the menu CSS, but I am not experienced enough with this to be sure of what I need to add.

Can someone take a look, and let me know if there’s a simple fix for this issue?

Code: http://pastebin.com/z2q8nUhX

Site: http://www.frenchbulldogvillage.net

I’ll try to add the code to this post, using the code markup option:

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