<Grid ShowGridLines="True">
        <Grid.RowDefinitions>
            <RowDefinition Height="1*"></RowDefinition>
            <RowDefinition Height="3*"></RowDefinition>
            <RowDefinition Height="1*"></RowDefinition>
        </Grid.RowDefinitions>
        <TextBlock Grid.Row="0"
                   HorizontalAlignment="Center"
                   Text="Заголовок экрана" />
        <Grid Grid.Row="1"
              ShowGridLines="True">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="1*"></ColumnDefinition>
                <ColumnDefinition Width="2*"></ColumnDefinition>
            </Grid.ColumnDefinitions>
            <Grid Grid.Column="0"
                  ShowGridLines="True">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition></ColumnDefinition>
                    <ColumnDefinition></ColumnDefinition>
                </Grid.ColumnDefinitions>

            </Grid>
            <Button Grid.Column="1"
                    Content=" Button"
                    Margin="70,20,70,0"></Button>
        </Grid>
        <Grid Grid.Row="2"
              ShowGridLines="True">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="2*"></ColumnDefinition>
                <ColumnDefinition Width="1*"></ColumnDefinition>
            </Grid.ColumnDefinitions>
        </Grid>
    </Grid>