<!DOCTYPE html>
<html>
<head>
   <meta charset="UTF-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>www.woelk.org</title>
   <style>
      body {
         margin: 0;
         padding: 0;
         /* 100% viewport height */
         height: 100vh;
         display: flex;
         justify-content: center;
         align-items: center;
         background-color: #000000;
         font-family: sans-serif;
         color: silver;
      }
      .content {
         text-align: center;
      }
   </style>
</head>
<body>
   <div class="content">
      <h1>Blank page</h1>
      <p>http://www.woelk.org</p>
   </div>
</body>
</html>