html, body { 
  height: 100%; 
  margin: 0; 
  overflow: hidden;
}
body { 
  display: flex; 
  align-items: center; 
  justify-content: center;
  background: #000; 
}
main {
  display: flex;
}
p {
  line-height: 1;
}
span {
  display: block;
  width: 2vmax; 
  height: 2vmax; 
  font-size: 2vmax; 
  color: #9bff9b11;
  text-align: center;
  font-family: "Helvetica Neue", Helvetica, sans-serif;
}
div#container {
    position:absolute;
    top:50%;
    left:50%;
    width:550px;
    height:500px;
    margin-left:-275px;
    margin-top: -250px;
    color:#000;
    font-weight:bold;
    padding:0;
}