JSFiddle - React, Tailwind, and code Playground

by lollero

HTML

<div id="button_line"></div>
    
<div id="wrap">
    <div id="button"></div>
</div>

CSS

body, html {
    margin: 0px;
    padding: 0px;
    background: #e1e1e1;
}

#wrap { 
    width: 400px;
    margin: 0px auto;
    background: #ffffff;
    position: relative;
    z-index: 10;
    
    height: 600px;
}

#button,
#button_line {
    position: absolute;
    top: 40px;
    right: 0px;
    height: 20px;
    background: #3a99ff;
}

#button {
    width: 100px;
}

#button_line {
    left: 50%;
    z-index: 5;
}