Accordion Arrow disappearing on published site

I have made an accordion style symbol with text information under a video. In these I put some small black arrow-images that rotate according to if it is open or closed. These show up perfectly when displayed on a read-only link or published to address (see below) however when I publish it / export it does not display (see below). I played around with size parameters but cannot get it to work. On mobile phones the the arrows are replaced by little rectangles.

Does anyone know how to fix this?

  1. Here is my site Read-Only:

  2. Published

  3. Published site (arrows disappearing):


Anyone has any idea?