JSFiddle - React, Tailwind, and code Playground

HTML

<div> test content would be here <hr> </div>

CSS

div{
    border-top: 1px solid;
    border-left: 1px solid;
    border-right: 1px solid;
    min-height: 100px;
    position:relative;
    }
    hr{
    width:100%;
    position:absolute;
    bottom:0;
    left:0;
    right;
    top:90%;
    }