AuthAndDB/practice/MainWindow.xaml

<Window x:Class="practice.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:practice"
        mc:Ignorable="d"
        Title="Вход" Height="300" Width="200" ResizeMode="NoResize">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="2*"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="2*"/>
            <RowDefinition Height="1.5*"/>
        </Grid.RowDefinitions>
        <Label Grid.Row="0" Content="Авторизация" HorizontalAlignment="Center" VerticalAlignment="Center" FontSize="18"/>
        <Label Grid.Row="1" Content="Логин" FontSize="14"/>
        <TextBox x:Name="log" Grid.Row="2" Height="20" Width="150"/>
        <Label Grid.Row="3" Content="Пароль" FontSize="14"/>
        <PasswordBox x:Name="pas" Grid.Row="4" Height="20" Width="150"/>
        <Button Grid.Row="5" Content="Вход" Height="30" Width="100" Click="Auth_Click"/>

    </Grid>
</Window>