[Dark Mode] The dotnet line of button is black in DarkMode

[Zheng-Li01]

.NET version

.NET 11 11.0.100-rc.2.26470.101-win-x64 build

Did it work in .NET Framework?

Not tested/verified

Did it work in any of the earlier releases of .NET Core or .NET 5+?

This is a regression, working well on .NET 10.0 build

Issue description

The dotnet line of button is black in DarkMode

Steps to reproduce

1. Create a .NET Winforms project with a Button control
2. Set app under Dark mode in program.cs file
   Application.SetColorMode(SystemColorMode.Dark);
3. Build & run the application
4. Observe the dotnet line of button after Tab to it