JSFiddle - React, Tailwind, and code Playground

HTML

<html>
<head>

</head>
<body>
<input type="text" />
<div id="box">
    / move 
</div>
</body>
<html>

CSS

body { font-size: 12px; line-height: 12px; font-family: arial;}
    #box { width: 100px; height: 15px; position: absolute; top: 35px; left: 0px; background: pink;}

JavaScript

$(document).ready(function(){
    var letter_size = 6;
    $("input[type='text']").keyup(function(e) {
        move_size = $(this).val().length * letter_size;
        $('#box').css({'left': move_size+'px'});
    });
});