Border color for multiple choice for single answer and multiple answers are not changing to black

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Border color for multiple choice for sing answer and multiple answers are not changing to black on click. Below is the code used for "Minimal 3D - Green" template (attached is the image)

.Skin label.MultipleAnswer.q-checked, .Skin label.SingleAnswer.q-checked {

border-color: black;

}

.Skin label.MultipleAnswer:hover, .Skin label.SingleAnswer:active {
border-color: black !important;
}

however on hover it is working :

.Skin label.MultipleAnswer:hover, .Skin label.SingleAnswer:hover {
border-color: black !important;
}