QFD2/QFluentWidgets/qss/dark/info_bar.qss

InfoBar {
    border: 1px solid rgb(29, 29, 29);
    border-radius: 6px;
    background-color: rgb(39, 39, 39);
}

#titleLabel {
    font: 14px 'Segoe UI', 'Microsoft YaHei';
    font-weight: bold;
    color: white;
}

#contentLabel {
    font: 14px 'Segoe UI', 'Microsoft YaHei';
    color: white;
}

InfoBar[type="Info"] {
    background-color: rgb(39, 39, 39);
}

InfoBar[type="Success"] {
    background-color: rgb(57, 61, 27);
}

InfoBar[type="Warning"] {
    background-color: rgb(67, 53, 25);
}

InfoBar[type="Error"] {
    background-color: rgb(68, 39, 38);
}

InfoBarCloseButton {
    background-color: transparent;
    border-radius: 5px;
}

InfoBarCloseButton:hover {
    background-color: rgba(255, 255, 255, 9);
}

InfoBarCloseButton:pressed {
    background-color: rgba(255, 255, 255, 6);
}