Change style of pyside6 ComboBox

Question

I have tried to style my pyside6 combobox like in the picture bellow but have not found a good solution. The problem is that the bottom corners from the dropdown have a square under it which is not transparent and the top does not connect the way i want it to connect with the main combobox. At the top the two are not seamlessly connected. Here is an image of what i want to achieve. Is that even possible?

My app does only run on windows and i have not set the fusion style.

I tried something like that but it did not really work:

QComboBox {
    border-radius: 10px;
    padding: 5px 5px 5px 5px;
    background-color: #2c2c2c;
    color: white;
    border: 1px solid #474747;
    min-width: 80px;
}

QComboBox::drop-down {
    width: 0px;
    border: none;
}

QComboBox::down-arrow {
    image: none;
}

QComboBox QAbstractItemView {
    border-bottom-right-radius: 10px;
    border-bottom-left-radius: 10px;
    background: #2c2c2c;
    border: 1px solid gray;
    padding: 4px 4px 4px 4px;
    outline: none;
}

All help is appreciated.