CSS test drive-like service that mimics browsers?

I don't know how to explain this but, basically, what im looking for is some kind of environment or program that can take my CSS for a "test drive" replicating a browser so I know what kind of outcome to expect once it's uploaded, does this exists? Kind of like having a preview of the CSS rule sets but having also the option , and have it render in a preview/development environment, while selecting a internet browser. Hope im getting through :-)