html, body {
  font-family: Arial, Helvetica, 'Sans Serif';
}
body {
  background: url('../img/back.jpg') no-repeat top center fixed;
  -webkit-background-size: 100%; 
  -moz-background-size: 100%; 
  -o-background-size: 100%;
  background-size: 100%;
}
div {
  margin: 20px auto;
  text-align: center;
  width: 450px;
  background: #ffffff;
  padding: 10px;
}
p {
  text-align: left;
}