How to set a different background-color to a disabled button with QSS?

Question

I have already tried to use disabled and !enabled but it doesn't work. Here is my QSS code :

QPushButton {
    background-color:#44c767;
    border-radius:5px;
    border:1px solid #18ab29;
    color:#ffffff;
    font-family:arial;
    font-size:15px;
    font-weight:bold;
    text-decoration:none;
    padding-right:10px;
    outline: 0;
}

QPushButton:hover:!pressed {
    background-color:#54d777;
}

QPushButton: pressed {
    background-color:#30b252;
}

QPushButton: disabled {
    background-color:#ff0000;
}

QPushButton: !enabled {
    background-color:#ff0000;
}

The documentation refers to a disabled pseudo state but without providing more information about it.

Edit

I am using QT5.3

Tripartite

Answer 1

Remove all spaces after colons (really ALL - because it invalidates the further css text) and it will work:

QPushButton:disabled {
background-color:#ff0000;
}

Actually, both disabled and !enabled works.

Catholicity

Many thanks! This is so stupid! The worst thing is that the little help box on the bottom of the style sheet editor told me that the QSS code was valid ... – Tripartite