inven/Inventory/MainWindow.xaml

<Window x:Class="Inventory.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:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
        xmlns:local="clr-namespace:Inventory"
        mc:Ignorable="d"
        Title="MainWindow" WindowStartupLocation="CenterScreen" AllowsTransparency="True" Background="Transparent" WindowStyle="None" ResizeMode="NoResize" Height="450" Width="350" Icon="Image/logo.png">
    <Grid MouseDown="Grid_MouseDown" KeyDown="Grid_KeyDown" >
        <Border BorderThickness="0" Background="#516DF6" CornerRadius="35"/>
        <Border BorderThickness="0" Background="#F6F8FC" CornerRadius="35" Margin="10,181,10,10"/>
        <Image Source="Image/logo.png" Margin="82,0,86,300"/>
        <Label Content="Инвентаризация" HorizontalAlignment="Center" FontFamily="Century Gothic" VerticalAlignment="Center" FontSize="24" Foreground="#F6F8FC" Width="210" Margin="70,137,70,275"/>
        <StackPanel Orientation="Vertical" Margin="50,212,46,42">
            <Label Content="Авторизация" HorizontalAlignment="Center" FontWeight="Bold" Margin="0,0,0,0" FontFamily="Century Gothic" FontSize="20"/>
            <StackPanel Orientation="Horizontal" Margin="0,15,0,0">
                <materialDesign:PackIcon Margin="0,0,0,0" Kind="User" Height="35" Width="35"/>
                <TextBox x:Name="logintxt" Margin="5,0,0,0" FontFamily="Century Gothic" Foreground="Black" materialDesign:HintAssist.Hint="Введите логин" materialDesign:TextFieldAssist.UnderlineBrush="Black" FontSize="18" MaxLength="15" Width="214" TextChanged="Logintxt_TextChanged"/>
            </StackPanel>
            <StackPanel Orientation="Horizontal" Margin="0,10,0,0">
                <materialDesign:PackIcon Margin="0,0,0,0" Kind="Password" Height="35" Width="35"/>
                <PasswordBox x:Name="passwordpsw" Margin="5,0,0,0" FontFamily="Century Gothic" materialDesign:TextFieldAssist.UnderlineBrush="Black" Foreground="Black" materialDesign:HintAssist.Hint="Введите пароль" FontSize="18" MaxLength="15" Width="214" PreviewKeyDown="Passwordpsw_PreviewKeyDown" PreviewTextInput="Passwordpsw_PreviewTextInput"/>
            </StackPanel>
            <Button x:Name="Vhod" Margin="0,25,0,0" materialDesign:ButtonAssist.CornerRadius="10" HorizontalAlignment="Center" FontSize="18" Background="#516DF6" BorderThickness="0" FontFamily="Century Gothic" Content="Войти" Height="31" Width="111" Click="Vhod_Click"/>
        </StackPanel>
        <Button x:Name="Exit" Style="{StaticResource MaterialDesignFloatingActionButton}" Background="Transparent" BorderThickness="0" BorderBrush="Transparent" Margin="299,10,10,396" Height="Auto" Width="Auto" Click="Exit_Click">
            <materialDesign:PackIcon BorderThickness="0" Kind="ExitToApp" Foreground="#F6F8FC" Height="30" Width="30" materialDesign:RippleAssist.Feedback="Transparent"/>
        </Button>
    </Grid>
</Window>