#html, body {
  top: 0px;
  right: 0px;
  bottom: 0px;
  left: 0px;
  width:600px;
  height: 100%;
  margin: auto;
  background-color:#DFE1F2;
}

h1 {
   text-align: center;
   color: black;
}

ul {
   margin-left: 3em;
}