The content for your alert is edited in the section (Content > Sections) Alert Button.

You can add any kind of text, links, or buttons in the content field. Assign the image you'd like to display via the image field. 

You can swap out the alert's content anytime you need to!

In the section Alert Button, a on/off checkbox has been added in. Simply check the Hide Popup box to hide the alert from your site, and uncheck the box to put it back on your site!