WPF Grid, remove highlight of cell click - wpf

Question

I have a window like this
<Window x:Class="Värvivärten_Sendscreen.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:Sendscreen"
mc:Ignorable="d"
Title="Sendscreen" Height="768" Width="1024" Background="white" ResizeMode="NoResize" KeyDown="Window_KeyDown" WindowStartupLocation="Manual" FontFamily="Ubuntu" Foreground="#2B2525">
<Window.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="Transparent" />
<SolidColorBrush x:Key="{x:Static SystemColors.ControlBrushKey}" Color="Transparent" />
</Window.Resources>
<DockPanel>
<DockPanel DockPanel.Dock="Left" VerticalAlignment="Center" Height="768" >
<StackPanel HorizontalAlignment="Left" Margin="20,0">
<Image Source="/logo.png" Width="156" Margin="-170,20,0,0"/>
<StackPanel Orientation="Horizontal" Margin="60,50,0,0" >
<Image Source="/estonia.png" Width="40" Height="40"></Image>
<TextBlock TextWrapping="WrapWithOverflow" Width="300" FontSize="14" Padding="20,0,0,0">Smart text
</TextBlock>
<Label></Label>
</StackPanel>
<StackPanel Orientation="Horizontal" Margin="60,20,0,0" >
<Image Source="/united-kingdom.png" Width="40" Height="40"></Image>
<TextBlock TextWrapping="WrapWithOverflow" Width="300" FontSize="14" Padding="20,0,0,0">Smart text
</TextBlock>
</StackPanel>
<StackPanel Orientation="Horizontal" Margin="60,20,0,0" >
<Image Source="/latvia.png" Width="40" Height="40"></Image>
<TextBlock TextWrapping="WrapWithOverflow" Width="300" FontSize="14" Padding="20,0,0,0">Smart text
</TextBlock>
</StackPanel>
<StackPanel Orientation="Horizontal" Margin="60,20,0,0" >
<Image Source="/russia.png" Width="40" Height="40"></Image>
<TextBlock TextWrapping="WrapWithOverflow" Width="300" FontSize="14" Padding="20,0,0,0">Smart text
</TextBlock>
</StackPanel>
<StackPanel HorizontalAlignment="Left" Margin="60,100">
<Image Source="/qr.png" Width="82"></Image>
<Label FontWeight="Bold">Smart text</Label>
<Label Margin="0,-10">Smart text</Label>
</StackPanel>
</StackPanel>
</DockPanel>
<StackPanel DockPanel.Dock="Bottom">
<Label FontWeight="Bold" FontSize="48" HorizontalContentAlignment="Center" Margin="0,50,0,50" >Smart text</Label>
<ListView x:Name="TvBox" BorderThickness="0" Background="white" VerticalAlignment="Center" Panel.ZIndex="4">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<Grid HorizontalAlignment="Center" VerticalAlignment="Center" >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="115*"></ColumnDefinition>
<ColumnDefinition Width="115*"></ColumnDefinition>
<ColumnDefinition Width="115*"></ColumnDefinition>
<ColumnDefinition Width="115*"></ColumnDefinition>
<ColumnDefinition Width="115*"></ColumnDefinition>
<ColumnDefinition Width="115*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="115*"></RowDefinition>
<RowDefinition Height="115*"></RowDefinition>
</Grid.RowDefinitions>
</Grid>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemContainerStyle>
<Style>
<Setter Property="Grid.Column"
Value="{Binding ColumnIndex}" />
<Setter Property="Grid.Row"
Value="{Binding RowIndex}" />
</Style>
</ItemsControl.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Vertical" Margin="0">
<Image Source="{Binding ImageData}" Margin="0" Width="115" MouseDown="Image_MouseDown" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<Image x:Name="BigImage" Width="400" Margin="0,40,0,0"></Image>
</StackPanel>
</DockPanel>
</Window>
All of the small images that are bound are clickable by this. I would like to remove the background highlight and border from them when clicked. How can I do so?