JSFiddle - React, Tailwind, and code Playground

HTML

<div class="c">
    <div class="m">111</div>
    sdf
</div>
<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs<p>sfs

CSS

.c {
    position:relative;
    top:200px;
    left:100px;
    background:green;
    width:200px;
    height:200px;
}
.m {
    position:fixed;
    margin-left:-30px;
    width:30px;
    height:30px;
    background:red;
}