JSFiddle - React, Tailwind, and code Playground

by kiokotzu

HTML

<section class="clearfix">
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
</section>

CSS

.clearfix:before,.clearfix:after {content: " ";display: table;}
.clearfix:after {clear: both;}
.clearfix {*zoom: 1;}

section{width:398px;border:1px solid blue;}
div{width:50px; height:50px;background:green; float:left;
  margin:5px 8px 5px 0;}

JavaScript

$(document).ready(function(){
    var numero = 6;
    $('div').each(function(index){
        if(index == numero){
            $(this).css({
                'marginRight':'0px',
                'background':'red'
            });
            numero=numero + 7;
        }
    });
});