<Window x:Class="CustomPanels.OverlapWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:CustomPanels"
        Title="4 elementy Button w OverlapPanel">
    <local:OverlapPanel>
        <Button FontSize="40" Content="1" Background="Red"/>
        <Button FontSize="40" Content="2" Background="Orange"/>
        <Button FontSize="40" Content="3" Background="Yellow"/>
        <Button FontSize="40" Content="4" Background="Lime"/>
    </local:OverlapPanel>
</Window>
