To add the class one to the first marker div element

Tell us what’s happening:
Describe your issue in detail here.

  **Your code so far**
/* file: index.html */
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Colored Markers</title>
  <link rel="stylesheet" href="styles.css">
</head>
<body>
  <h1>CSS Color Markers</h1>
  <div class="container">
    <div class="marker" class="one">
    </div>
    <div class="marker">
    </div>
    <div class="marker">
    </div>
  </div>
</body>
</html>
/* file: styles.css */
h1 {
text-align: center;
}

.marker {
width: 200px;
height: 25px;
background-color: red;
margin: 10px auto;
}

  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36

Challenge: Step 16

Link to the challenge:

You don’t need to repeat the class attribute, simple add to the existing class attribute with the other class name you want to add, but remember to seperate the with a space.