15/21 Can't arrange the background


I'm trying to arrange the background image but I'm getting this message:
Oops, try again. expected body to have its background-position style equal to 50% 50% but got 50%.

This is what I have:

<!DOCTYPE html>



body {
    background: url("https://codecademy-content.s3.amazonaws.com/courses/web-beginner-en-3pc6w/images/splash.jpg");
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    text-align: center;
    color: white;
    font-family: Helvetica;




<img src="https://codecademy-content.s3.amazonaws.com/courses/web-beginner-en-3pc6w/images/avatar.jpg" height="250" width="250">

<p>Hi! I am learning how to make my very own web page! I really like blueberry muffins and long walks on the beach.</p>

<input type="email" placeholder="Email">
<input type="submit">



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