如何将样式表应用于QPushButton的菜单

QPushButton *menuButton = new QPushButton("菜单");
menuButton->setMenu(new QMenu(menuButton));

menuButton->setStyleSheet("QPushButton {"
                          "background-color: #F5F5F5;"
                          "border: 1px solid #CCCCCC;"
                          "padding: 5px;"
                          "}"
                          "QPushButton::menu-indicator {"
                          "image: url(indicator.png);"
                          "subcontrol-position: right center;"
                          "subcontrol-origin: padding;"
                          "}"
                          "QMenu {"
                          "background-color: white;"
                          "border: 1px solid #CCCCCC;"
                          "}"
                          "QMenu::item {"
                          "padding: 5px 30px 5px 20px;"
                          "}"
                          "QMenu::item:selected {"
                          "background-color: #E5E5E5;"
                          "}");

QMenu *menu = menuButton->menu();
menu->addAction("菜单项1");
menu->addAction("菜单项2");
menu->addAction("菜单项3");