Mobile menu is black on black

Hello all, I have recently started building a website at :johnwardmusiclessons.com

Everything looks good so far other than when viewing the site on a mobile device my drop down menu is black on black, so you cant see any of the links.

Please help me!

I am using the fanwood light theme if that is relevant.

Thanks!!!

ps. I would prefer to avoid code if possible, but I am very good with
cntrl-v if pointed in the right direction.