title: Mask Image with disappearing text
body: <p>I want to have a background and a mask which lie on top of each other. So the visitor has an impression of an normal background image. But when the visitor scrolls down the text/navbar is sticky and floats behind the image (in relation to the movement). I have seen an similiar effect on this Website <a href="http://aganaplocha.com/netmag/mountains/" rel="nofollow noreferrer">http://aganaplocha.com/netmag/mountains/</a> but it doesn't work on mine <a href="https://www.bemase.com/gallery(1)" rel="nofollow noreferrer">https://www.bemase.com/gallery(1)</a>.</p>
  <p>I am happy for generally or specific tips/solutions.
  I am new into coding and just doing it since a few weeks, so maybe the solution ain't that difficult.</p>
  <p>Thanks</p>