<Button
       HorizontalOptions="FillAndExpand"
       Text="English"
       Clicked="English_OnClicked"
       Style="{StaticResource wizardButton}"/>

<Style x:Key="wizardButton" TargetType="Button" BasedOn="{StaticResource buttonStyle}">
            <Setter Property="BackgroundColor" Value="#3FFF" />
            <Setter Property="BorderColor" Value="#FFFF" />
            <Setter Property="TextColor" Value="#CFFF" />
            <Setter Property="BorderWidth" Value="2" />
        </Style>
<Style x:Key="buttonStyle" TargetType="Button">
            <Setter Property="TextColor" Value="White" />
            <Setter Property="BorderRadius" Value="4" />
            <Setter Property="FontSize" Value="Medium" />
            <Setter Property="BackgroundColor" Value="{StaticResource grayDark}" />
            <Setter Property="HeightRequest">
                <Setter.Value>
                    <OnPlatform x:TypeArguments="x:Double" iOS="40" Android="50" />
                </Setter.Value>
            </Setter>
        </Style>