CSS-improve capability with browser fallback

please my reputales mentors, how do I get through this stage of CSS coding challenge? sreenshort below:

What have you tried? You don’t seem to have added any code. Did you try searching the forum first?

When asking for help on challenges please use the “Ask for help” button instead of posting screenshots. It will make a new thread and post your code for you.

thanks. I’ve tried inputing some codes as follow:
:root {
–red-color: red;
.red-box {
background: red;
background: var(–red-color, red);
height: 200px;

. Please, what are the exact codes to add to get me through is challenge.

Almost, but you have added something you were not asked to add.

Can you see what it is?
background: var(--red-color, red);

You shouldn’t change the existing code, only add the required line, this is stopping you from passing the tests. If you can’t remember what you changed then reset code and just add the fallback again