Minor improvements on the docs

docs/en/Localization.md

@@ -162,8 +162,8 @@ Getting the localized text is pretty standard.
 
 Just inject the `IStringLocalizer<TResource>` service and use it like shown below:
 
-````C#
-public class MyService
+````csharp
+public class MyService : ITransientDependency
 {
     private readonly IStringLocalizer<TestResource> _localizer;
 

docs/en/UI/AspNetCore/Customization-User-Interface.md

@@ -1,6 +1,6 @@
 # ASP.NET Core (MVC / Razor Pages) User Interface Customization Guide
 
-This document explains how to override the user interface of a depended [application module](../../Modules/Index.md) for ASP.NET Core MVC / Razor Page applications.
+This document explains how to override the user interface of a depended [application module](../../Modules/Index.md) or [theme](Theming.md) for ASP.NET Core MVC / Razor Page applications.
 
 ## Overriding a Page