Controls going outside of window - xaml

Question

I'm attempting to make a "information" page, but when I get to a finished product this happens:
Video of application
So as you can see the poster of the movie and the description is fine to start with, but when the user attempts to use a different size than default it doesn't resize so the the user can see the same information.
Code:
<Grid>
<Image
Name="Backdrop"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Stretch="UniformToFill" />
<Grid Background="{ThemeResource SystemControlAcrylicElementBrush}">
<StackPanel Margin="80">
<StackPanel Orientation="Horizontal">
<Button Click="ButtonBase_OnClick" Style="{StaticResource MaterialDesignRaisedLightButton}">
<SymbolIcon Symbol="Back" />
</Button>
<TextBlock
Margin="20,0,0,0"
VerticalAlignment="Center"
Style="{StaticResource TitleTextBlockStyle}"
Text="{x:Bind Movie.Title}" />
</StackPanel>
<Border
Margin="0,10,0,10"
VerticalAlignment="Bottom"
BorderBrush="Gray"
BorderThickness="1"
Style="{StaticResource DownwardDropShadow}" />
<StackPanel
HorizontalAlignment="Center"
VerticalAlignment="Center"
Orientation="Horizontal">
<StackPanel>
<Grid>
<Image
Name="Poster"
MinWidth="200"
MaxWidth="500"
Margin="10" />
<Button
Width="100"
Height="100"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Background="{ThemeResource SystemControlAcrylicElementBrush}"
CornerRadius="100">
<Viewbox MaxWidth="60" MaxHeight="60">
<SymbolIcon Foreground="Gray" Symbol="Play" />
</Viewbox>
</Button>
</Grid>
</StackPanel>
<StackPanel
MinWidth="300"
MaxWidth="600"
Padding="20">
<TextBlock Style="{StaticResource PageTitleStyle}" Text="Information" />
<Border
Margin="0,10,0,10"
VerticalAlignment="Bottom"
BorderBrush="Gray"
BorderThickness="1"
Style="{StaticResource DownwardDropShadow}" />
<TextBlock
Style="{StaticResource BodyTextStyle}"
Text="{x:Bind Movie.Overview}"
TextWrapping="WrapWholeWords" />
</StackPanel>
</StackPanel>
</StackPanel>
</Grid>
</Grid>
So in short, how do I keep the design, but make is so when the window changes size the image & text resizes to stay inside the window and stay visible.

Answer 1

Controls going outside of window
The problem is that when set root panel as StackPanel , the size of children element will be fixed. And it will not change as the window size changes. For solve the this, you could try to use Grid to replace. Please refer the following xaml layout.
<Grid>
<Image
Name="Backdrop"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Source="Assets/hello.jpg"
Stretch="UniformToFill"
/>
<Grid Background="{ThemeResource SystemControlAcrylicElementBrush}">
<Grid Margin="80" >
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="9*" />
</Grid.RowDefinitions>
<StackPanel Orientation="Horizontal">
<Button Click="ButtonBase_OnClick">
<SymbolIcon Symbol="Back" />
</Button>
<TextBlock
Margin="20,0,0,0"
VerticalAlignment="Center"
Style="{StaticResource TitleTextBlockStyle}"
Text="Grid Test Page"
/>
</StackPanel>
<Border
Margin="0,10,0,10"
VerticalAlignment="Bottom"
BorderBrush="Gray"
BorderThickness="1"
/>
<Grid
Grid.Row="1"
Margin="0,20,0,0"
HorizontalAlignment="Center"
VerticalAlignment="Top"
>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Grid>
<Image
Name="Poster"
MinWidth="200"
MaxWidth="500"
Margin="10"
Source="Assets/hello.jpg"
/>
<Button
Width="100"
Height="100"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Background="{ThemeResource SystemControlAcrylicElementBrush}"
CornerRadius="100"
>
<Viewbox MaxWidth="60" MaxHeight="60">
<SymbolIcon Foreground="Gray" Symbol="Play" />
</Viewbox>
</Button>
</Grid>
<StackPanel
Grid.Column="1"
MinWidth="300"
MaxWidth="600"
Padding="20"
>
<TextBlock Text="Information" />
<Border
Margin="0,10,0,10"
VerticalAlignment="Bottom"
BorderBrush="Gray"
BorderThickness="1"
/>
<TextBlock Text="Defines a flexible grid area that consists of columns and rows. Child elements of the Grid are measured and arranged according to their row/column assignments (set by using Grid.Row and Grid.Column attached properties) and other logic." TextWrapping="WrapWholeWords" />
</StackPanel>
</Grid>
</Grid>
</Grid>
</Grid>