Improve Compatibility with Browser Fallbacks--need help

Tell us what’s happening:
I don’t know what to do. I am trying to add another declaration before the existing one and I have to insure that the declaration is red.

Your code so far

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

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36.

Nice try!

If you are using var keyword, you are referring to a variable. However, there is no variable named red. So you just want to call it straight red instead of var(red).

Thanks for the help. I got it now.