.body,html{
    margin: 0px;
    height: 100%;
    width: 100%;
}

.bg{
    background-image: url("clever.jpg");

  /* Full height */
  height: 100vh; 
  width: 100vw;

  /* Center and scale the image nicely */
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}