Tell us what’s happening:
Your code so far
<style>
:root {
--red-color: red;
}
.red-box {
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/72.0.3626.119 Safari/537.36
.