JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
    <div class="post"></div>
</div>

CSS

#wrapper {
    width: 3000px;
    height: 40px;
}

.post {
    width: 150px;
    height: 40px;
    background: red;
    margin: 10px;
    float: left;}

JavaScript

$(function(){
    $(window).bind('scroll', function() {
        $('.post').each(function() {
            var post = $(this);
            post.text( post.position().left );
        });        
    });
});