Improve Compatibility with Browser Fallbacks - I need help

HTML-CSS
1

Tell us what’s happening:

Can someone explain this?

Your code so far


<style>
  :root {
    --red-color: red;
  }
  .red-box {
    background: var(red)!important; 
    background: var(--red-color);

    height: 200px;
    width:200px;
  }
</style>
<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.

Link to the challenge:
https://learn.freecodecamp.org/responsive-web-design/basic-css/improve-compatibility-with-browser-fallbacks

2

Well, that wouldn’t work. But, remember how you would set a background to the color red before learning about variables? That is what a browser that is not able to read variables would use

3

I’m still not sure…

4

Do you mean like using CSS selectors?

5

I mean the value you would but after the column. Just make the background red without using the variables, like you would have done before learning variables exist in css