Step 49. change background-colour to background

I’m pretty sure I have the correct code for this one however error tells me I haven’t done it. cannot pass. any suggestions?

  **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" type="text/css" href="styles.css">
</head>
<body>
  <h1>CSS Color Markers</h1>
  <div class="container">
    <div class="marker red">
    </div>
    <div class="marker green">
    </div>
    <div class="marker blue">
    </div>
  </div>
</body>
</html>
/* file: styles.css */
h1 {
text-align: center;
}

.container {
background-color: rgb(255, 255, 255);
padding: 10px 0;
}

.marker {
width: 200px;
height: 25px;
margin: 10px auto;
}

.red {
background: rgb(255, 0, 0);
}

.green {
background-color: #007F00;
}

.blue {
background-color: hsl(240, 100%, 50%);
}

  **Your browser information:**

User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.1.2 Safari/605.1.15

Challenge: Step 49

Link to the challenge:

are you using safari or extentions, they are known to create problems, stick chrome

Change the browser and see if it will pass