I’ve edited your code 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.
See this post to find the backtick on your keyboard.
Note: Backticks (`) are not single quotes (').
Note: Be sure to add
<link rel="stylesheet" href="styles.css">in your HTML to link your stylesheet and apply your CSS
I do not see a link to the CSS and you are missing all the boilerplate in the HTML you posted. (doctype, head, html, body)