:root {
  --note-size: 20em;
}

html,
body,
#board {
  min-height: 100% !important;
  height: 100%;
}

#board h2 {
  font-weight: bold;
  font-size: 2rem;
}
#board p {
  font-family: "Reenie Beanie";
  font-size: 2rem;
}
#board,
#board li {
  list-style: none;
}
#board {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
}
#board li a {
  text-decoration: none;
  color: #000;
  background: #ffc;
  display: block;
  height: var(--note-size);
  width: var(--note-size);
  padding: 1em;
  box-shadow: 5px 5px 7px rgba(33, 33, 33, 0.7);
  transform: rotate(-6deg);
  transition: transform 0.15s linear;
}

#board li:nth-child(even) a {
  transform: rotate(4deg);
  position: relative;
  top: 5px;
  background: #cfc;
}
#board li:nth-child(3n) a {
  transform: rotate(-3deg);
  position: relative;
  top: -5px;
  background: #ccf;
}
#board li:nth-child(5n) a {
  transform: rotate(5deg);
  position: relative;
  top: -10px;
}

#board li a:hover,
#board li a:focus {
  box-shadow: 10px 10px 7px rgba(0, 0, 0, 0.7);
  transform: scale(1.25);
  position: relative;
  z-index: 5;
}

#board li {
  margin: 1em;
}