Can I create a design for the audio player?

Hello. I would like to change the design of the default audio player. Which files should I modify?

For Omeka Classic, there’s a plugin “HTML5 Media” that pulls in a differently-styled player.

Otherwise, Omeka just uses the browser’s default player for audio and video. There’s things you can do with CSS to change the appearance of those default players, but at a certain level you’re probably talking about more complex options like using a JS library to replace the interface, and possibly a plugin or module to change the markup.