body {
  margin: 0;
  min-height: 100vh;
  background: #05010f;
  color: #eafffb;
  font-family: 'Trebuchet MS', Verdana, sans-serif;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 16px;
  box-sizing: border-box;
}

h1 {
  margin: 8px 0 4px 0;
  text-shadow: 0 0 12px #33ff99, 0 0 24px #33ff99;
}

.instructions {
  margin: 4px 0 12px 0;
  color: #b9ffe9;
  text-align: center;
}

canvas {
  background: #000010;
  border: 3px solid #33ff99;
  border-radius: 8px;
  box-shadow: 0 0 30px rgba(51, 255, 153, 0.5);
  max-width: 100%;
  height: auto;
  touch-action: none; /* stop the browser from scrolling/zooming when dragging on the canvas */
}

canvas:fullscreen,
canvas:-webkit-full-screen {
  width: 100vw;
  height: 100vh;
  max-width: 100vw;
  max-height: 100vh;
  object-fit: contain;
  border-radius: 0;
}

@media (max-width: 700px) {
  body { padding: 6px; }
  h1 { font-size: 1.2rem; margin: 4px 0 2px 0; }
  .instructions { font-size: 0.7rem; margin: 2px 0 6px 0; }
}