Code editor and preview don't match up

I have been working on the CSS Grid challenges and when I do the challenges in the editor it looks fine, but when I try to preview the same code in my CoffeeCup HTML Editor or another code editor, the preview does not display the grid. This is happening with each challenge (i.e., grid-template-columns/rows, and so on). It seems that the browser/s do not display any of the code for the grid code that I apply. As I said, it works in the challenges but not in the real world for some reason.

You got any screen shots or codes we could see?