JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <div id="blue-box"></div>

</div>

CSS

#container {
 position:relative;
    width:700px;
 height:1000px;
    top:50px;
    left:50px;
 background-color:yellow;
    
}

#blue-box{
    position:fixed;
    width:100px;
    height:100px;
    background-color:blue;
    margin-top:20px;
    margin-left:400px;