Pictures Megamenu : where?

The images in our Megamenu show problems..
I cannot upload an image here..

Question : where can I find, change the colours behind the menu -titles?

Our mega menu
HOME : viewed correctly - where do I find the ' mouse over' blue button?
CONTACT US : OK
SEARCH : viewed with error, where can I find the blue button?
WHY CHOOSE... : ok, only the green button is square and first had rounded corners
GLOBAL NETWORK : ok, only the grey button is square and first had rounded corners
LANGUAGES : viewed with error, where can I find the blue button?

I added this information.

What is your IP so I can whitelist.

Please empty cache and try again.

I have no options left. Can you use Teamviewer please?
If you set the time, I can set it up in seconds..