Fix WindowsRegistryKey for Qt 6.8.1 (#154)

Daniel

2024-12-06 91274c58b1772dfe38d3fcab291693141e822684

 examples/mainwindow/light-style.qss

@@ -144,6 +144,10 @@
    background-color: #F3F3F3;
}

MainWindow[custom-style=true] {
    background-color: transparent;
}

QWidget#clock-widget {
    font-size: 75px;
    color: #333333;