ASP.NET MVC where did ::before ::after go?

Question

css

Wrote html+css page and transferred it to ASP.NET.
All is well, except for one thing - ::before ::after suddenly disappeared somewhere. They are written in the CSS itself, but they are simply not in the inspector (F12).
Have they been replaced with something in the platform, or should it be somehow included in the configs?

Can anyone come across..