html,
body.youzi-fullpage {
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background: #0b1020 !important;
  position: fixed !important;
  inset: 0 !important;
  display: block !important;
}

body.youzi-fullpage #GameDiv,
body.youzi-fullpage #Cocos3dGameContainer,
body.youzi-fullpage #GameCanvas {
  display: block !important;
  width: 100% !important;
  height: 100% !important;
}

.demo-back-btn {
  position: fixed;
  z-index: 9999;
  top: max(10px, env(safe-area-inset-top));
  left: max(10px, env(safe-area-inset-left));
  padding: 8px 14px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 999px;
  background: rgba(8, 12, 24, 0.72);
  color: #fff;
  font: 600 13px/1.2 "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  cursor: pointer;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.demo-back-btn:active {
  transform: scale(0.98);
}