je veux changer la couleur de foreground flyout page .  <FlyoutPage
    x:Class="MauiAppPharmacieDotNet7.AppShell"
    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
    xmlns:local="clr-namespace:MauiAppPharmacieDotNet7"   
    xmlns:Pages="clr-namespace:MauiAppPharmacieDotNet7"
    BackgroundColor="CadetBlue"
    >
   
    <FlyoutPage.Flyout>
        
        <ContentPage Title="Master page" BackgroundColor="White">

            <StackLayout>
                <!--Entete Menu lateral-->
                <Grid RowDefinitions="*" HeightRequest="150" BackgroundColor="WhiteSmoke">

                    <Label Text="Pharmacie" 
                           TextColor="DarkCyan"
                           VerticalOptions="Center"
                           HorizontalOptions="Center"
                           FontSize="30"
                           FontAttributes="Bold"
                           BackgroundColor="Transparent"/>


                </Grid>
                <!--Les element du  Menu lateral-->
                <Line HeightRequest="1" 
                      BackgroundColor="LightGray"/>
                <!--Gestion des vente-->
                <Grid x:Name="GridVentesMenu" 
                      ColumnDefinitions="25*,75*" 
                       Padding="5,5,0,5">
                    <Image Source="sale.png"
                           Grid.Column="0"
                           HeightRequest="40"
                           WidthRequest="40"/>
                    <Label Text="Gestion des ventes"
                           TextColor="black"
                           Grid.Column="1"
                           VerticalOptions="Center"
                           FontAttributes="Bold"
                           FontSize="16"/>
                    <Grid.GestureRecognizers>
                        <TapGestureRecognizer Tapped="GridVenteTapped"/>
                    </Grid.GestureRecognizers>

                </Grid>
                <Line HeightRequest="1"
                      BackgroundColor="LightGray"/>
                <!--Gestion des achats-->
                <Grid  x:Name="GridAchatsMenu"
                      ColumnDefinitions="25*,75*" 
                      Padding="5,5,0,5">
                    <Image Source="purchase.png"
                       Grid.Column="0"
                       HeightRequest="40"
                       WidthRequest="40"/>
                    <Label Text="Gestion des Achats"
                           TextColor="Black"
                           Grid.Column="1"
                           VerticalOptions="Center"
                           FontAttributes="Bold"
                           FontSize="16"
                          
                    />
                    <Grid.GestureRecognizers>
                        <TapGestureRecognizer Tapped="GridAchatsTapped"/>
                    </Grid.GestureRecognizers>
                </Grid>
                <Line HeightRequest="1" BackgroundColor="LightGrey"/>
            </StackLayout>



        </ContentPage>
    </FlyoutPage.Flyout>

    <FlyoutPage.Detail>
        <NavigationPage>
            <x:Arguments>
                <local:MainPage/>
            </x:Arguments>
        </NavigationPage>
    </FlyoutPage.Detail>
    
</FlyoutPage>