Please read this post to learn how to properly format code in posts on the forum.
Has an extra < should be <html>
This code looks fine, you said its in the same folder so it should work.
At the end of the file should be closing html tag which looks like this: </html>
Please make the above changes, save it and if the CSS is still not working, paste in the updated HTML code as well as your CSS code and a screenshot of what the result looks like
the < and /> are not actually in the code but where accidentally added when I posted the message. Code looked fine to me too thats why I am a bit confused