* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body {
  margin: 0; height: 100%; overflow: hidden; touch-action: none;
  background: radial-gradient(circle at 50% 30%, #1b2d5e, #060b1a);
  user-select: none; -webkit-user-select: none;
}
#app { width: 100vw; height: 100vh; }
canvas { display: block; }