.douyin_content {
  position: relative;
}

.div_mengceng {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  width: 100%;
  height: 100%;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.6);
}

.douyin_img {
  width: 300px;
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 5000;
  object-fit: contain;
}