<header>Header</header>
<div class="container">
  <section class="main">
    <h1>Main Section (Section Principale)</h1>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Ducimus, qui totam placeat ullam eligendi itaque perferendis similique aliquam inventore tenetur. Eveniet quisquam unde vitae expedita voluptates soluta in obcaecati recusandae.</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Magnam, voluptas autem sed a rem impedit quidem facere dolore praesentium optio provident minus deleniti eveniet ex cum fuga perferendis illum molestiae!</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Asperiores, repellendus, nobis hic molestias eveniet perferendis nesciunt voluptate ipsum impedit quo a veritatis porro qui commodi expedita? Nostrum enim sed ab.</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Eos, aspernatur reiciendis animi sequi ducimus odit ad quos libero fugiat vitae natus optio dolores reprehenderit enim aliquid necessitatibus deleniti voluptatum quod.</p>
    <p>
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Nobis, cumque, eveniet, veritatis, quae esse delectus non omnis incidunt nihil saepe labore neque fugiat praesentium. Nulla quam pariatur eos hic tempore.
    </p>
  </section>
  <aside>
    <h1>Sidebar (Barre latérale)</h1>
    <p>La barre latérale n'a pas autant de contenu que la section principale de gauche, et pourtant elle se développe à la même hauteur.</p>
  </aside>
</div>
<footer>Footer</footer>
body {
  color: #555;
  font-size: 1.1em;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

header,
footer {
  height: 100px;
  line-height: 100px;
  text-align: center;
  background-color: #ccc;
}

section,
aside {
  background-color: #594255;
  color: #eee;
  padding: 3em 1.5em;
  margin: 1% 0;
}

section {
  -webkit-flex: 2 1 500px;
  -webkit-box-flex: 2;
  -ms-flex: 2 1 500px;
  flex: 2 1 500px;
  margin-right: 1%;
}

aside {
  -webkit-flex: 1 2 250px;
  -webkit-box-flex: 1;
  -ms-flex: 1 2 250px;
  flex: 1 2 250px;
}

.container {
  -webkit-display: -webkit-box;
  -webkit-display: -webkit-flex;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-align-items: stretch;
  -webkit-box-align: stretch;
  -ms-flex-align: stretch;
  align-items: stretch;
}

@media screen and (max-width: 500px) {
  .container {
    -webkit-flex-direction: column;
    -webkit-box-orient: vertical;
    -webkit-box-direction: normal;
    -ms-flex-direction: column;
    flex-direction: column;
  }
  section {
    margin-right: 0;
    -webkit-flex-basis: auto;
    -moz-flex-basis: auto;
    -ms-flex-preferred-size: auto;
    flex-basis: auto;
  }
}

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