Kuripko13/MainWindow.xaml

<Window x:Class="Progect_Kuripko.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Progect_Kuripko"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="42"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="42"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="295"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>
        <Grid HorizontalAlignment="Left" Height="419" Margin="470,0,0,0" VerticalAlignment="Top" Width="65" Grid.Column="1" Grid.RowSpan="3"/>
        <Grid HorizontalAlignment="Left" Height="100" Margin="84,72,0,0" VerticalAlignment="Top" Width="100" Grid.Column="1" Grid.Row="1"/>
        <Rectangle Fill="#FFF4F4F5" HorizontalAlignment="Left" Height="42" Grid.Row="2" StrokeThickness="0" VerticalAlignment="Top" Width="792" Grid.ColumnSpan="3"/>
        <Button Content="Назад" Name="ButtonBack" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="75" Click="Button_Click"/>
        <Frame x:Name="MainFrame" Content="Frame" HorizontalAlignment="Left" Height="335" Grid.Row="1" Source="Pages/AuthPage.xaml" Navigated="MainFrame_Navigated" VerticalAlignment="Top" Width="792" Grid.ColumnSpan="3"/>
        <Label Content="Label" HorizontalAlignment="Left" Margin="127,72,0,0" Grid.Row="1" VerticalAlignment="Top"/>
    </Grid>
</Window>