I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.
You can also use the “preformatted text” tool in the editor (</>) to add backticks around text.
Technically, CSS properties are not case sensitive in most situations (or maybe all of them, I don’t have time to research if there are exceptions). So in this case, it is the tests that are case sensitive.
Realistically, everyone uses all lowercase for CSS properties and you will probably get funny looks if you don’t follow this convention as well. So I would just make it a habit to always use all lowercase for CSS properties.