html, body {
  height: 100%;
  width: 100%;
  font-family: Helvetica, sans-serif;
  color: #FFFFFF;
  font-size: 100%;
  padding: 0;
  margin: 0;
  letter-spacing: 0.2rem;
  overflow: hidden;
  background: #000000; 
  background: -webkit-linear-gradient(to bottom, #434343, #000000);  /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to bottom, #434343, #000000); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
}

div#main {
  position: absolute;
  top: 0;
  left: 0;
  padding: 1.6rem;
}

canvas#canvas {
  background: #000000;  /* fallback for old browsers */
  background: -webkit-linear-gradient(to bottom, #434343, #000000);  /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to bottom, #434343, #000000); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
}

div.controller {
  position: absolute;
  bottom: 0;
  left: 0;
  padding: 1.6rem
}