#chessBoard {
  max-width: 400px;
}

.buttons {
  margin: 0.5em 0;
}

header {
  display: flex;
  justify-content: space-between;
}
nav {
  margin: 1em;
}

nav a {
  border: 3px solid darkblue;
  background: lightskyblue;
  padding: 0.25em;
}
nav a:hover {
  color: white;
  background: darkblue;
}