Waveform appearance in dark mode

[JulianKniephoff]

@lkiesow wrote in https://github.com/elan-ev/opencast-studio/pull/1069#issuecomment-1691166632:

I think the black waveform box looks a bit odd. Especially since there is already a box around that box. Can we try switching to the same background color as the inner box? Something like this:

@oas777 replied in TODO:

I consider this a canvas holding a box (cf. editor) and I wouldn't want this removed, at least not in the light mode:

Discuss!

[LukasKalbertodt]

Personally, I don't think it's a problem and I would just keep it as is. If no one else will comment here agreeing with Lars in the next while, I will close this issue (to clean the issue list a bit).

[narickmann]

I would leave it as it is. Without the box, it feels like sth is missing (at least a border). As a compromise, you could make the box a little brighter (i.e. a dark gray, but only in dark mode)? But then we could have too little contrast.

[lkiesow]

I think what's weird is that you essentially have a box in a box, with both having a different background color.