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

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #05060f;
  font-family: 'Rajdhani', system-ui, -apple-system, sans-serif;
  -webkit-user-select: none;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  touch-action: none;
  overscroll-behavior: none;
}

#stage {
  position: fixed;
  inset: 0;
}

#game {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  cursor: crosshair;
}

.icon-btn {
  position: fixed;
  top: max(12px, env(safe-area-inset-top));
  width: 46px;
  height: 46px;
  border-radius: 14px;
  border: 1px solid rgba(160, 200, 255, 0.22);
  background: rgba(10, 14, 34, 0.6);
  color: #cfe8ff;
  font-size: 18px;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 20;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: transform 0.08s ease, background 0.15s ease;
}
.icon-btn:active { transform: scale(0.92); background: rgba(30, 40, 80, 0.8); }
#btn-pause { right: max(70px, calc(env(safe-area-inset-right) + 70px)); }
#btn-mute  { right: max(12px, calc(env(safe-area-inset-right) + 12px)); }

@media (max-width: 480px) {
  .icon-btn { width: 40px; height: 40px; font-size: 15px; border-radius: 12px; }
  #btn-pause { right: max(60px, calc(env(safe-area-inset-right) + 60px)); }
}