Add a base resource for styles common with light and dark.
ADD
WalletWasabi.Fluent/Styles/Themes/Base.xaml
+<Styles xmlns="https://github.com/avaloniaui"
+ xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+ xmlns:sys="clr-namespace:System;assembly=netstandard"
+ xmlns:local="clr-namespace:AvalonStudio.Controls.Standard.CodeEditor;assembly=AvalonStudio.Controls.Standard">
+ <Styles.Resources>
+ <Color x:Key="SystemAccentColorLight1">#FF82C690</Color>
+ <Color x:Key="SystemAccentColorLight2">#FF92CF9E</Color>
+ <Color x:Key="SystemAccentColorLight3">#FFA2D8AD</Color>
+ <Color x:Key="SystemAccentColorDark1">#FF5BA96C</Color>
+ <Color x:Key="SystemAccentColorDark2">#FF449556</Color>
+ <Color x:Key="SystemAccentColorDark3">#FF2E8041</Color>
+ <Color x:Key="SystemAccentColor">#FF72BD81</Color>
+ </Styles.Resources>
+</Styles>

MODIFY
WalletWasabi.Fluent/Styles/Themes/BaseDark.xaml
WalletWasabi.Fluent/Styles/Themes/BaseDark.xaml
<BoxShadows x:Key="BoxShadow">0 1 4 #121212</BoxShadows>
</Styles.Resources>
<StyleInclude Source="avares://Avalonia.Themes.Fluent/Accents/FluentDark.xaml"/>
+ <StyleInclude Source="avares://WalletWasabi.Fluent/Styles/Themes/Base.xaml" />
</Styles>

MODIFY
WalletWasabi.Fluent/Styles/Themes/BaseLight.xaml
WalletWasabi.Fluent/Styles/Themes/BaseLight.xaml
<BoxShadows x:Key="BoxShadow">0 1 4 #D1D1D1</BoxShadows>
</Styles.Resources>
<StyleInclude Source="avares://Avalonia.Themes.Fluent/Accents/FluentLight.xaml"/>
+ <StyleInclude Source="avares://WalletWasabi.Fluent/Styles/Themes/Base.xaml" />
</Styles>

Add a base resource for styles common with light and dark.