body {
  color: orange;
  font-family: "Serif";
  background-image: linear-gradient( black,grey);
  background-repeat: no-repeat;
  background-attachment: fixed; 
  background-size: cover;
  background-color: grey;
  text-align: center;
}
  
h1, h2, h3, h4, h5, h6 {
  text-align: center;
  color: green;
}

a, img {
 text-align: center;
  color: #00ffff;
  }