Avalonia/tests/Perspex.Markup.Xaml.UnitTests/Xaml/Style2.xaml

<Style xmlns="https://github.com/perspex"
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
       xmlns:mut="https://github.com/perspex/mutable">
  <Style.Resources>
    <mut:SolidColorBrush x:Key="RedBrush" Color="{StyleResource Red}"/>
    <mut:SolidColorBrush x:Key="GreenBrush" Color="{StyleResource Green}"/>
    <mut:SolidColorBrush x:Key="BlueBrush" Color="{StyleResource Blue}"/>
  </Style.Resources>
</Style>