i am using ee for the first time, and i try to make a web design explanatory website, but I have a problem that the word 'css' cannot be used for template group name because it is a reserved word. I tried /CSS/ but it works only when the address is typed as .com/CSS/ ~ I want to use css instead of CSS. How can I do?
Lol, use the word stylesheet or styles. Why are you trying to break all of the eggs in the carton? You'll run into a lot of roadblocks going the route you want to...
Also, at the end of the day, you are going to not want to do all your stylesheet editing, or any template editing, in your browser. You should use an ftp client and your preferred editor, saving templates as files. I would suggest getting your development tool-chain in order now, before you go down the rabbit hole.
To be clear, you can't do what you want. It would require insane core EE modification. Pick a different name for that group, or use your assets/css folder and edit them with a tool-chain solution.