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

body {
  font-size: 15px;
  font-family: Calibri, Helvetica, Arial, sans-serif;
  color: #fff;
  background: url(images/Silvia-Glanzmann-Walther.jpg) no-repeat center center #000;
  background-size: cover;
}

.wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding: 50px 20px;
}

a {
  color: #fff;
  font-weight: bold;
}
a:hover {
  color: #000;
  background: #fff;
}