"Sticky" header image in Harlowe?

Ah, yeah, I don’t know why I didn’t get that.

OK, I think your second one should work except that you’re not setting the background on the tw-include[type="header"] element.

tw-include[type="header"] {
  background-image: url(header.png);
  background-size: contain;
  background-repeat: no-repeat;
  width: 100vw;
  height: 100vh;
  position:fixed;
  left: 0;
  top: 0;
  z-index: 2;
  margin: 0;
  padding: 0;
}

Then you’ll still want to put some padding at the top of tw-story so the bar doesn’t hide the start of the text, but that should get you close, I think?