I have tried to remove the scan lines from the header, footer and the showcase as per your instructions on the video, however each time, nothing changes.
I have copied the details from the encounters parent CSS and then pasted them onto the child in CSS but nothing happens.
For the top header, this is on the Showcase banner area, to hide the lines is found on the Header tab in the customizer; the top logo header area is on the Basic Settings tab. I did not do one for the footer though and I probably should have. I will add this to my next update that I am working on at the moment. As for the footer, there should be no lines there.