It's semitransparent, so it will fit your page's background automatically. Moreover, you can easily change the player color (or even set a custom background image) by adding a "background" style property to the code!
I've also been working on a design refresh for the player's default skin.
It's glossy and has a 10% transparency, so that it can always look "white" but less dramatic on dark backgrounds. Setting the player's background won't work for it (which is not so bad, as it is supposed to be white).
The fallback preview image comes from a stock by clandestine-stock on deviantArt. Thanks to the original author!