html,
body {
  width: 100%;
  height: 100%;
  margin: 0;
  overflow: hidden;
  background: #000;
}

#video {
  display: block;
  width: 100%;
  height: 100%;
  background: #000;
}

.message {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 1.5rem;
  color: #f5f5f5;
  font: 0.95rem/1.5 system-ui, sans-serif;
  text-align: center;
  background: rgba(0, 0, 0, 0.82);
}

.message[hidden] {
  display: none;
}