I am using jMediaelement for a customized HTML5 audio player. Unfortunately, client now needs a vertical volume slider.
When calling the jMediaelement API, I can only use this markup:
<div class="volume-slider" title="volume slider"></div>
…which will be replaced by a horizontal volume slider.
How can I adjust the volume handle to be vertical (from bottom=silent to top=loud)?

PS: I already opened an issue at Sourceforge, however, no answer yet.
Fortunately, Alexander replied to the question himself.
Here’s his working solution: