.loader {
  width: 100%;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  font-family: ZhuqueFangsong, "Microsoft JhengHei", "Microsoft Yahei",
    sans-serif;
  font-size: 30px;
  animation: l1 1s linear infinite alternate;
  overflow: hidden;
}

.loader:before {
  content: "载入中...";
}

@keyframes l1 {
  to {
    opacity: 0;
  }
}