inabox/InABox.Avalonia/Theme/Classes/ListBox.axaml

<Styles xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:avalonia="clr-namespace:InABox.Avalonia">
        
    <Style Selector="ListBoxItem">
        <Setter Property="Padding">
            <avalonia:ThicknessProvider Left="0" Right="0" Top="0" Bottom="0" />
        </Setter>
    </Style>
    
    <!--  PointerOver State  -->
    <Style Selector="ListBoxItem:pointerover /template/ ContentPresenter#PART_ContentPresenter">
        <Setter Property="Background" Value="Transparent" />
    </Style>
</Styles>