I have one javascript file i.e. test.js and one Css file i.e. style.css. I want to call this JS file through CSS

The javascript can call the CSS but not the other way around. Can you explain in more detail what you are trying to achieve?

The javascript file can load itself, assign parts of itself to watch for events on elements, selected by CSS if you like and when it observes something interesting it can jump in and enhance the user experience.

Or to put it another way, it doesn't need CSS.

Thanks Dear....