Editopia/Editopia.Editor/App.xaml

<Application xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
  <Application.Styles>

    <Style Selector="TextBlock.h1">
      <Setter Property="Foreground" Value="#212121"/>
      <Setter Property="FontSize" Value="20"/>
      <Setter Property="FontWeight" Value="Medium"/>
    </Style>

    <Style Selector="TextBlock.h2">
      <Setter Property="Foreground" Value="#727272"/>
      <Setter Property="FontSize" Value="13"/>
    </Style>
    <StyleInclude Source="resm:Avalonia.Themes.Default.DefaultTheme.xaml?assembly=Avalonia.Themes.Default"/>
    <StyleInclude Source="resm:Avalonia.Themes.Default.Accents.BaseLight.xaml?assembly=Avalonia.Themes.Default"/>
    <StyleInclude Source="resm:Editopia.Editor.SideBar.xaml"/>
  </Application.Styles>
</Application>