* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: "Courier New", monospace;
  background: #1b1b24;
  color: #eee;
  display: flex;
  justify-content: center;
  padding: 30px 15px;
}

#app {
  width: 100%;
  max-width: 620px;
  text-align: center;
}

h1 {
  margin-bottom: 20px;
}

.hidden {
  display: none;
}

button {
  font-family: inherit;
  font-size: 16px;
  background: #3a3a4d;
  color: #eee;
  border: 2px solid #55556b;
  border-radius: 6px;
  padding: 10px 18px;
  margin: 6px;
  cursor: pointer;
}

button:hover:not(:disabled) {
  background: #4c4c66;
}

button:disabled {
  opacity: 0.4;
  cursor: default;
}

#status {
  margin-bottom: 14px;
  font-size: 18px;
  min-height: 24px;
}

#board {
  display: inline-block;
  text-align: left;
  font-family: "Courier New", monospace;
  font-size: 14px;
  line-height: 1.4;
  background: #111116;
  color: #eee;
  border: 2px solid #55556b;
  padding: 10px;
  margin: 0 auto;
}

#controls {
  margin: 18px 0;
}

.legend {
  font-size: 13px;
  opacity: 0.85;
}