change group box color pyqt5 code example

Example: change group box color pyqt5

QGroupBox {
    background-color: red;
    margin-top:1em;
}
QGroupBox QGroupBox {
    background-color: green;
}
QGroupBox::title {
    subcontrol-origin: padding;
    subcontrol-position: left top;
    background: transparent;
    margin-top: -2.5em;
}