JSFiddle - React, Tailwind, and code Playground

HTML

<div id="box-1"></div>
<div id="box-2"></div>

CSS

#box-1{
    overflow: hidden;
    width: 10px;
    box-sizing: border-box;
    height: 100px;
    margin-bottom: 10px;
    background: black;
    border-right: 10px solid red;
}
#box-2{
    overflow: hidden;
    width: 0px;
    box-sizing: border-box;
    height: 100px;
    background: black;
    border-right: 10px solid red;
}