How to implement custom color changes on content page?
Lets say I’ve got

<Grid
    x:Name="TopOverlay"
    AbsoluteLayout.LayoutBounds="0,0,1,0.08"
    AbsoluteLayout.LayoutFlags="WidthProportional,HeightProportional"
    BackgroundColor="{DynamicResource Background}"

And Label

<Label
    Padding="7,0"
    FontAutoScalingEnabled="False"
    FontSize="{Binding Source={RelativeSource AncestorType={x:Type local:ModalReaderViewModel}}, Path=FontSize}"
    LineBreakMode="WordWrap"
    Text="{Binding .}"
    TextColor="{DynamicResource DarkerTextColor}"

I need to change these Background and DarkerTextColor values as user picks. There will be 3 different option, each will contain different colors for background and label.

Saw some approaches using AppTheme binding, but I need more custom options, maybe in future there appear 4-5 different themes, so how could i create ‘myOwn’ theme binding sort to say?