body {
  font-family: sans-serif;
  max-width: 800px;
  margin: auto;
  padding: 1em;
  background-color: #f9f9f9;
  color: #333;
}

#main {
  background-color: #d1d1d1;
  max-width: 80%;
  margin: 0px auto ;
  padding: 10px 20px;
}

/*This class is for centred pictures*/
.picturediv {
  display: flex;
  justify-content: center;
}

/*This class is for centred header text*/
.header {
  text-align: center;
}