absolute layout on horizontal layout - xamarin

Question

I am trying to het the same view for portrait and for horizontal. I need the box view to be in the middle of the grey stack layout its ok on portrait but once I switch to horizontal layout the aquamarine box view Is at the end of the stacklayout. How do I get it in the middle for both layouts?
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:AbsolutePath"
x:Class="AbsolutePath.MainPage">
<AbsoluteLayout>
<AbsoluteLayout.Padding>
<OnPlatform x:TypeArguments="Thickness">
<On Platform="iOS">0, 20, 0, 20</On>
</OnPlatform>
</AbsoluteLayout.Padding>
<!--<BoxView Color="LightGray"
AbsoluteLayout.LayoutBounds="0, 0, 1, .35"
AbsoluteLayout.LayoutFlags="All"/>-->
<StackLayout AbsoluteLayout.LayoutBounds=".1, .10, 1, .50" BackgroundColor="LightGray"
AbsoluteLayout.LayoutFlags="All">
<Label Text="$11.95"
TextColor="Black"
FontSize="11"
FontAttributes="Bold"
HorizontalOptions="Start"/>
<BoxView HeightRequest="200" BackgroundColor="Aquamarine" VerticalOptions="Center"
WidthRequest="350"
HorizontalOptions="Center"/>
</StackLayout>
<StackLayout AbsoluteLayout.LayoutBounds="0, 1, 1, .65"
AbsoluteLayout.LayoutFlags="All"
Padding="0, 10, 0, 0">
<Label Text="Transaction History"
FontSize="15"
FontAttributes="Bold"
HorizontalOptions="Center"/>
<ListView>
<ListView.ItemsSource>
<x:Array Type="{x:Type x:String}">
<x:String>Transaction Item +$15.00 9/9/19</x:String>
<x:String>Transaction Item +$15.00 9/9/19</x:String>
<x:String>Transaction Item +$15.00 9/9/19</x:String>
<x:String>Transaction Item +$15.00 9/9/19</x:String>
<x:String>Transaction Item +$15.00 9/9/19</x:String>
<x:String>Transaction Item +$15.00 9/9/19</x:String>
</x:Array>
</ListView.ItemsSource>
</ListView>
</StackLayout>
</AbsoluteLayout>
</ContentPage>