2 Tier Dropdown Menu

Hello,

I am working on adding a code into the code injection that will allow me to have multiple dropdown levels in my navigation link. However whenever I try to paste the code into code injection, a gray bar shows up and goes all the way down the page. Could someone help me, is the code I am using incorrect? Would be glad of any input on how to do this. 

Thank you in advance!😁

Which code do you use? Can you post here? We can help easier.