html, body {
  margin: 0 auto;
  padding: 0;
}
#help {
  box-sizing: border-box;
  border: 1px black solid;
  padding-left: 1em;
  padding-right: 1em;
  background: white;
  display: none;
  position: absolute;
  top: 100px;
  left: 100px;
  width: 520px;
  z-index: 100;
  box-shadow: 3px 3px 5px 5px rgba(50, 50, 50, 0.25);
}