Improve template navigation focus contrast

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Improve template navigation focus contrast

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Improve focus contrast for generated navigation links

Description

Generated Web and Blazor navigation links inherit Bootstrap’s translucent focus ring, producing only 1.285:1 contrast. Keyboard users with low vision may not be able to identify the focused link.

• Focus styling

  • Apply the existing opaque #258cfb focus ring to every .nav-link.
  • Cover MVC, Razor Pages, F# MVC, Blazor Web, and Blazor WebAssembly templates.

• Regression coverage

  • Verify that focused Blazor navigation links resolve to the opaque ring color.

.nav-link:focus {
  box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem #258cfb;
}

• Fixes Focus indicator has insufficient color contrast on "Home" and "Privacy" links.: A11y_.NET Core Cloud Platform (ASP.NET Core)_WebSample_NonTextContrast #68228