I was trying to customize GUI made in Qt Designer by calling QApplication::setStyleSheet() and got one strange feature: when I set in StyleSheet even one property for some widget, for example QLabel{background-color : red}, other properties of this widget that I have set for this widget in Designer (like font, alignment, etc...) are reset to defauls or to these of widget`s parent. If anybody could tell is this a normal behaviour or a bug, or maybe I do something wrong?