Make a pop up header bar for my divi theme wordpress site

I want a pop up header bar made for my divi theme wordpress site. I wish to copy the header bar of [login to view URL] . (the red pop up that says santa on it) I want you to create the exact same thing. The only difference, i'd like my pop up bar to appear above all of my sites content. Instructions. 1/Don't use wordpress plugins. No plugins. 2/ all css to go in child theme css or divi theme options css panel. 3/ any js code place in the child theme. (and code that is required to make this whole thing work must be in the child theme) 4/ copy the exact header bar, i will customise it after. 5/ make sure it appears above all site content on every device and is responsive. 6/ do a good job and i'll use you again. Thank you.