<Page loaded="loaded">
    <GridLayout rows="*" cols="*" verticalAlignment="center">

        <Button text="Tap me" tap="signIn" />    

        <Label text="Label text" /> 

    </GridLayout>
</Page>

Button {
    margin: 20;
    padding: 10;
    width: 50%;
    background-color: green;
    border-color: rgba(255,0,0,0.8); /* Doesn't work */
    border-color: rgb(255, 0, 0);  /* Doesn't work */
    border-color: red;  /* Works */
    border-color: #F00;  /* Works */
    border-width: 3;
}

Label {
    border-color: rgba(255,0,0,0.8); /* Doesn't work */
    border-color: rgb(255, 0, 0);  /* Doesn't work */
    border-color: red;  /* Works */
    border-color: #F00;  /* Works */
    border-width: 3;
}