Widgets background problem (styled with CSS)

Hello!
I need to set backgrounds for my widgets. I use the global css-file and set it using qApp->setStyleSheet.
At css-file, I need to set separately colors for all widgets and QTabWidget::pane subcontol. So I write:

Code:

---

QWidget
{
  background-color: blue;
  color: white;
}
 
QTabWidget::pane{
 border-top: 1px solid grey; 
 background-color: red;
}

---

The problem is - QWidget's style's background is preffered over QTabWidget::pane. If I comment out QWidget's background-color, the QTabWidget::pane background-color works fine and I see the red background. But if QWidget's background-color is set, the QTabWidget::pane will be the same as QWidget's background-color.
How to solve this problem?

I have the same problem in Qt5. Have you solved this problem?