JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
<!DOCTYPE html>
<html>

  <head>
    <title>Testing </title>
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
    <meta charset="utf-8">
    <link rel="stylesheet" type="text/css" href="../css/core.css">
    <link rel="stylesheet" type="text/css" href="../css/base.css">
    <link rel="stylesheet" type="text/css" href="../css/custom.css">
    <link rel="stylesheet" type="text/css" href="../css/animate.css">
    <link rel="icon" type="image/png" href="../favicon.png-v=2.html">
    <script src="../js/assets/jquery.js"></script>
    <script type="text/javascript" src="https://maps.google.com/maps/api/js?sensor=true"></script>
    <script type="text/javascript" src="../js/jquery.ui.map.js"></script>
    <script type="text/javascript" src="../js/contact.js"></script>
  </head>

  <body class="dark-hero boxed">
    <!-- page loader -->
    <div id="loader-container">
      <div class="clear-loading loading-effect-3">
        <div><span></span></div>
        <p><b>ME</b>
          <p>
      </div>
    </div>
    <div class="body-overlay"></div>


    <!-- Wrapper-->
    <div id="wrapper" class="container-fluid smooth-transition">

      <!-- Header-->
      <header>
        <div class="container">
   -- Menu-->
          <ul class="navbar-classic">
            <li><a href="index.html" class="active">Qui sommes-nous? </a>
            </li>
            <li><a href="index.html">Nos services aux <b>parters</b> & aux <b>institutionnels</b> </a>

            </li>

            <li><a href="index.html">E-shop </a>

            </li>

            <li><a href="#">Nous contacter  </a></li>
                        <li><a href="#" class="lang">FR/DE</a>
              <ul class="dropdown">
                <li><a href="../fr/index.html">Français</a></li>
                <li><a href="../de/index.html">Deutch</a></li>
              </ul>
         ...

CSS

@import url("https://fonts.googleapis.com/css?family=Work+Sans:400,500,300");
@import url("https://fonts.googleapis.com/css?family=Roboto+Mono:300,400,700");
* {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  box-sizing: border-box
}

::-moz-selection {
  background: #2e2e2e;
  color: #eee
}

::selection {
  background: #2e2e2e;
  color: #eee
}

a:active,
a:focus,
a:hover,
input:active,
input:focus,
input:hover,
textarea:active,
textarea:focus,
textarea:hover {
  outline: 0
}

body {
  font-family: Helvetica Neue, sans-serif;
  font-weight: 300;
  font-style: 16px;
  text-align: justify;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: Helvetica Neue, sans-serif
}

@media screen and (max-width:768px) {
  h1 {
    font-size: 2.3em
  }
}

.copyright,
p {
  font-weight: 200;
  font-size: 22px;
  line-height: 1.9
}

.copyright a,
p a {
  font-weight: 700;
  color: #2e2e2e
}

h1 {
  font-size: 3em
}

h2 {
  font-family: Helvetica Neue, sans-serif;
  font-size: 30px;
  margin: 10px 0 7px
}

h3 {
  font-size: 20px;
  margin-top: 0;
  color: #3b976e;
  font-weight: 300;
}

h4 {
  font-size: 1.3em;
  margin-bottom: 10px;
  font-family: Helvetica Neue, sans-serif
}

h5 {
  text-transform: uppercase
}

h5,
h6 {
  font-size: 1em
}

header .content,
section.content,
section .content {
  line-height: 2
}

header .content h1,
section.content h1,
section .content h1 {
  margin-bottom: 37px
}

header .content p,
section.content p,
section .content p {
  margin-bottom: 50px;
  line-height: 1.8
}

header .content p:last-child,
section.content p:last-child,
section .content p:last-child {
  margin-bottom: 0
}

header .content p a,
section.content p a,
section .content p a {
  color: #2e2e2e;
  font-weight: 700;
  border-bottom: 1px solid #2e2e2e
}

header .content p a.btn,
section.content p a.btn,
section .content p a.btn {
  border: 0
}

header .content p a.btn.btn-hollow,
section.content p a.btn.btn-hollow,
section .content p a.btn.btn-hollow {
  border:...