html,
body {
  height: 100%;
  background-color: rgb(3, 53, 15);
}

body {
  color: rgb(159, 214, 88);
  text-shadow: 0 .05rem .1rem rgba(0, 0, 0, .5);
  box-shadow: inset 0 0 5rem rgba(0, 0, 0, .5);
  margin: 0;
}


.container { 
    height: 100%;
    position: relative;
}
  
main {
    margin: 0;
    position: absolute;
    top: 50%;
    width: 100%;
    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
}

h1 {
    text-align: center;
}