Mobile site navigation buttons not working....

Hi,

Can you please take a look at ericksonasphalt.com on mobile and see what code you would need me to send you to see why the buttons aren't working.  They did work, and then I changed the color of the background and now they don't.  I am frustrated and at wits end with it.  I don't have the code home with me but I can screen shot a bunch tomorrow night if I know where even to start with.  I did not build the site, just working on it. 

TIA,

Vel