Code WPF Calculator

<Window x:Class="Calc1.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:Calc1"
        mc:Ignorable="d"
        Title="Supercalculator 1.0" Height="450" Width="400">
     <Grid Background="#FFBDE2DD">
          <TextBox x:Name="tb1" HorizontalAlignment="Left" Height="54" Margin="19,26,0,0" TextWrapping="Wrap" Text="123" VerticalAlignment="Top" Width="335" FontSize="36"/>
          <TextBox x:Name="tb2" HorizontalAlignment="Left" Height="54" Margin="19,85,0,0" TextWrapping="Wrap" Text="456" VerticalAlignment="Top" Width="335" FontSize="36"/>
          <TextBlock x:Name="tb3" HorizontalAlignment="Left" Margin="355,54,0,0" TextWrapping="Wrap" Text="+" VerticalAlignment="Top" FontSize="36" Foreground="#FFB998A3"/>
          <Button x:Name="b7" Content="7" HorizontalAlignment="Left" Margin="19,153,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="b8" Content="8" HorizontalAlignment="Left" Margin="87,153,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="b9" Content="9" HorizontalAlignment="Left" Margin="155,153,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="bPlus" Content="+" HorizontalAlignment="Left" Margin="223,153,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFAFB8CF"/>
          <Button x:Name="binus" Content="-" HorizontalAlignment="Left" Margin="291,153,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFAFB8CF"/>
          <Button x:Name="b4" Content="4" HorizontalAlignment="Left" Margin="19,212,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="b5" Content="5" HorizontalAlignment="Left" Margin="87,212,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="b6" Content="6" HorizontalAlignment="Left" Margin="155,212,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="bMozh" Content="*" HorizontalAlignment="Left" Margin="223,212,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFAFB8CF"/>
          <Button x:Name="bDil" Content="/" HorizontalAlignment="Left" Margin="291,212,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFAFB8CF"/>
          <Button x:Name="b1" Content="1" HorizontalAlignment="Left" Margin="19,271,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="b2" Content="2" HorizontalAlignment="Left" Margin="87,271,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="b3" Content="3" HorizontalAlignment="Left" Margin="155,271,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24"/>
          <Button x:Name="bClear" Content="С" HorizontalAlignment="Left" Margin="223,271,0,0" VerticalAlignment="Top" Width="131" Height="54" FontSize="24" Background="#FFAFB8CF"/>
          <Button x:Name="b0" Content="0" HorizontalAlignment="Left" Margin="19,330,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFD8B8B8"/>
          <Button x:Name="bKoma" Content="," HorizontalAlignment="Left" Margin="87,330,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFD8B8B8"/>
          <Button x:Name="bPlusMinus" Content="+/-" HorizontalAlignment="Left" Margin="155,330,0,0" VerticalAlignment="Top" Width="63" Height="54" FontSize="24" Background="#FFD8B8B8"/>
          <Button x:Name="bDorivnue" Content="=" HorizontalAlignment="Left" Margin="223,330,0,0" VerticalAlignment="Top" Width="131" Height="54" FontSize="24" Background="#FF50A6B4" Foreground="White"/>
     </Grid>
</Window>