avalonia_znak/AvaloniaApplication3/MainWindow.axaml

<Window xmlns="https://github.com/avaloniaui"
        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"
        mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
        x:Class="AvaloniaApplication3.MainWindow"
        Title="AvaloniaApplication3">

	<Grid Background="#2F2FA2">  
  <Image Source="C:\Users\user\Desktop\AvaloniaApplication3\AvaloniaApplication3\258c0307-f9a8-478e-8bc5-df632c8996ba.png" Stretch="Fill" />   
  <Border   
      HorizontalAlignment="Center" VerticalAlignment="Center"   
      CornerRadius="10"   
      Background="White"   
      Opacity="0.8"   
      Padding="20">   
      <StackPanel Name="WritePanel">   
          <StackPanel Margin="10">   
              <TextBlock>Добро пожаловать! Введите дату рождения </TextBlock>   
          </StackPanel>   
          <StackPanel Margin="10" HorizontalAlignment="Center">  
  <DatePicker x:Name="DatePicker"></DatePicker>   
          </StackPanel>   
          <StackPanel Margin="10" HorizontalAlignment="Center">   
              <Button x:Name="Button" Classes="test" Grid.Column="0" Grid.Row="0" Margin="5" Padding="10" FontSize="16">Узнать</Button>   
          </StackPanel>   
          <StackPanel Margin="10" HorizontalAlignment="Center">   
              <TextBlock Text="Что ты хочешь узнать?" TextAlignment="Center" FontSize="18" />   
          </StackPanel>   
          <Grid Margin="10">   
              <Grid.ColumnDefinitions>   
                  <ColumnDefinition Width="Auto" />   
                  <ColumnDefinition Width="*" />   
                  <ColumnDefinition Width="Auto" />   
              </Grid.ColumnDefinitions>   
              <Grid.RowDefinitions>   
                  <RowDefinition Height="Auto" />   
              </Grid.RowDefinitions>  
  <Button x:Name="ZodiacButton" Classes="test" Grid.Column="0" Grid.Row="0" Margin="5" Padding="10" FontSize="16">Знак Зодиака</Button>  
  <Button x:Name="ChineseZodiacButton" Classes="test" Grid.Column="2" Grid.Row="0" Margin="5" Padding="10" FontSize="16">Восточный Гороскоп</Button>   
          </Grid>   
          <StackPanel Margin="10">  
              <TextBlock x:Name="ResultTextBlock" Text="" TextAlignment="Center" FontSize="16" />  
  <TextBlock x:Name="ZodiacTextBlock" Grid.Column="0" Grid.Row="1" Margin="5" FontSize="16" />  
  <TextBlock x:Name="ChineseZodiacTextBlock" Grid.Column="2" Grid.Row="1" Margin="5" FontSize="16" />  
    
          </StackPanel>  
   
      </StackPanel>   
  </Border>   
</Grid>

</Window>