Isn't this more on the side of future fantasy than science fiction? Just a thought.
I read both the preview and the first chapter and story-wise, it seems to lack a certain "oomf" for some reason. And the story elements seem rather loose and I suppose, expects readers to just take what's thrown...
You could maybe just add some additional buffer space at the bottom of the page so that the user can still read everything else on the page on mobile even if the player + subtitle is floating in a fixed footer.
Oh yeah, I knew it was using the browser's built in player lol, just thought I'd...
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The subtitle text should always be visible while scrolling around the page (think a floating footer)
There should be an easier way to navigate through the player especially on mobile (for example, tap + backwards drag to go back a few seconds depending on the drag distance, same with...