WPF double line on the top of listbox - wpf

Question

I am new to wpf. I need to have a window that list all accounts added. But my application shows a double line below the "Accounts". Not sure what caused this. could someHow to fix this? Here is my xaml
<Grid>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<StackPanel x:Name="StackPanel1" Grid.Row="0" HorizontalAlignment="Left" Height="150" VerticalAlignment="Top" Width="444">
<TextBlock x:Name="AddAccountTextBlock" HorizontalAlignment="Left" TextWrapping="Wrap" VerticalAlignment="Top" Height="60" Width="369" Text="Add account to allow for simple access to your company resources
" SnapsToDevicePixels="True"/>
<Button x:Name="AddAccount" Content="Add Account" HorizontalAlignment="Left" VerticalAlignment="Top" Width="140" RenderTransformOrigin="0.466,0.977" IsCancel="True" Height="40" Foreground="White" Background="Blue" Click="OnAddAccount"/>
</StackPanel>
<StackPanel x:Name="StackPanel2" Grid.Row="2" HorizontalAlignment="Left" Height="154" Width="444">
<TextBlock x:Name="AccountsTextBlock" TextWrapping="Wrap" Text="Accounts" Height="25" Width="68" FontSize="16" FontFamily="Tahoma"/>
<ListBox x:Name="accounts" Height="130" VerticalAlignment="Top">
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="Height" Value="100"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<Border Name="_Border" BorderBrush="Gray" BorderThickness="0.5" SnapsToDevicePixels="true">
<ContentPresenter />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="true">
<Setter TargetName="_Border" Property="Background" Value="LightSkyBlue"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Image HorizontalAlignment="Left" VerticalAlignment="Center" Grid.Row="0" Grid.Column="0" Width="100" Source="{Binding Path=imagePath}" />
<TextBlock HorizontalAlignment="Center" VerticalAlignment="Center" Grid.Row="0" Grid.Column="1" Text="{Binding Path=userInfo}"></TextBlock>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</Grid>

Answer 1

You may remove the borders of the ListBox by setting the BorderThickness property:
<ListBox x:Name="accounts" Height="130" VerticalAlignment="Top" Margin="100"
BorderThickness="0">
You may set it to 1,0,1,0 to remove only the top and bottom borders. The order is left, top, right, bottom.