If you correctly included CSS, you can just right-click on website and Inspect Element. If something displays under styles (on the right or bottom side). It is included.
The code works in the html file. Does any know of a test tool which will tell me if my path to the external file is correct. Thanks
But I don't understand, if your code works well in HTML, why do you worry if the external file's path is correct? If it works in HTML, that means path is correct.
Are you simply seeking for a tool that would help you write CSS code? I don't think there's one, although you can install Brackets, which can hint you options for every role you choose. For example typing background-size:, will bring up 100%, 50%, stretch, cover, inherit. That might help you in learning.
In my opinion though, there's nothing better than learning it the hard way. On top of that, CSS isn't that hard that something bad will happen and if something does. You'll see that it's very easily noticable. And it's quite fun to play with it in order to fix it.
Thank you very much. I don't know what I did, but it works now. I will continue to work with Inspect Element. I am working on an app with python and django. I don't know why CSS was "kicking" me. thanks again.