Empty orange box by default in form on site

Hi

I am using the X theme with cornerstone and at the end of every form I have an empty orange box by default. It’s not very nice and I have no idea how to get rid of it. It appears on every form on the website even when I create a completely new form.

Thank you very much for your support.

Best regards

Orlo

The page I need help with: [log in to see the link]