/* override browser default */
html, body {
  margin: 0;
  padding: 0;
  background-color: black;
  height: 100%;
}

/* use viewport-relative units to cover page fully */
body {
  height:100%;
  width: 100%;
  overflow-x:hidden;
  overflow-y:hidden;
}

/* include border and padding in element width and height */
* {
  box-sizing: border-box;
}

/* full-sized  container that fills up the page */
div {
  height: 100%;
  width: 100%;

  /* example padding, font-size, background, etc */
  padding: 1px;
  font-size: 20px;
}