JSFiddle - React, Tailwind, and code Playground

by Egor Jvechkin

HTML

<div class="cl1 active">
 
</div>

SCSS

.cl1 {
   &.active:after { content: ''; display: block; position: absolute; bottom: 0; width: 100%; height: 3px; background: color-calc(amber, 0);
}