I have a QDialog that I use a stylesheet to set the background color to black.
e.g.
QDialog {background-color: black; }

However when I display a QMessageBox called from that dialog it inherits the stylesheet from the parent.

I would like to be able to revert to the default stylesheet of the QMessageBox to get the background color back to normal for the QMessageBox, but can't find a way to do so. I've tried setting the stylesheet to:
QDialog { }
and
QMessageBox {}
and that doesn't work. I can set the background to another color implicitly, e.g.:
"QDialog { background-color: white;}"
, but want to use the default for the platform.

Any suggestions on how to do this? Is there a way to reset a particular style back to the default instead of what it inherited from it's parent?