body {
  margin: 0;
  overflow: hidden;
  background: black;
  font-family: Arial, sans-serif;
}

canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
}

h1 {
  position: absolute;
  top: 40px;
  left: 40px;
  color: white;
  font-size: 40px;
  z-index: 2;
}

button {
  position: absolute;
  top: 120px;
  left: 40px;
  padding: 14px 24px;
  background: white;
  border: none;
  cursor: pointer;
  z-index: 2;
}