JSFiddle - React, Tailwind, and code Playground

HTML

<div id="outer">
<div id="content"></div>
</div>

CSS

* {
    margin: 0 auto;
}


#outer {
    width: 200px;
    height: auto;
    
}


#content {
    width: 200px;
    height: 100%;
    position: absolute;
    background-color: green;
    bottom: 0;
   
}