Learn CSS Variables by Building a City Skyline - Step 4

Tell us what’s happening:
Describe your issue in detail here.
What have I done wrong? The link was already self-closed, but the code did not pass.

  **Your code so far**
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>City Skyline</title>
  <link rel="stylesheet" href="styles.css" />
</head>
<body>
</body>
</html>
  **Your browser information:**

User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.36

Challenge: Learn CSS Variables by Building a City Skyline - Step 4

Link to the challenge:

It is accepted in my browser. Maybe try resetting the steps?