Hi again,
I've changed the background colour for this theme in the theme settings. But know I discovered accidentally, that - although I have done this - in the style.css is still the original background colour, that comes with the original theme files (#edeeef).
At the frontend site, the colour is as I set it in the theme settings, so far, so good. But I don't understand, where BigFeature writes this background colour down, if not in the style.css ... I'm a bit confused, sorry ...