Can someone please tell me what is wrong with this code?

Tell us what’s happening:

Your code so far

:root {
  --red-color: red;
.red-box {

  background: var(--red-color);
  height: 200px;
:root {
  --green-color: green;
  background: green;
  background: var(--green-color);
  height: 100px;
  width: 100px;
<div class="red-box"></div>
<div class="green-box"></div>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.105 Safari/537.36.

Challenge: Improve Compatibility with Browser Fallbacks

Link to the challenge:

You didn’t describe what problem you’re having.

You were only suppose to add another background declaration and set it to color red.