新人求助qwq关于QMenuBar的问题

Customizing QMenuBar
QMenuBar is styled as follows:
QMenuBar {
background-color: qlineargradient(x1:0, y1:0, x2:0, y2:1,
stop:0 lightgray, stop:1 darkgray);
}
QMenuBar::item {
spacing: 3px; /* spacing between menu bar items */
padding: 1px 4px;
background: transparent;
border-radius: 4px;
}
QMenuBar::item:selected { /* when selected using mouse or keyboard */
background: #a8a8a8;
}
QMenuBar::item:pressed {
background: #888888;
}