Body background

Tell us what’s happening:
what’s wrong in this? please anyone.

Your code so far

<style>
body {
  background-color: black;
}
</style>

Your browser information:

Your Browser User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.79 Safari/537.36 Edge/14.14393.

Link to the challenge:
https://www.freecodecamp.org/challenges/style-the-html-body-element

It works. What is the problem?