JSFiddle - React, Tailwind, and code Playground

HTML

<div class="content">Contenu du site</div>

CSS

html, body {
  height: 100%;
  margin: 0; padding: 0;
}

body {
  background: repeating-linear-gradient(90deg, #606dbc, #606dbc 10px, #465298 10px, #465298 20px);
}

.content {
  width: 70%;
  height: 100%;
  margin: 0 auto;
  background: #eee;
}