三个...动画

<div class="loading-dots">
  <span></span>
  <span></span>
  <span></span>
</div>

　　

.loading-dots {
  text-align: center;
}

.loading-dots span {
  display: inline-block;
  margin: 0 5px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: #ccc;
  animation: loading-dots 1.5s infinite;
}

.loading-dots span:nth-child(2) {
  animation-delay: 0.5s;
}

.loading-dots span:nth-child(3) {
  animation-delay: 1s;
}

@keyframes loading-dots {
  0% {
    transform: scale(0);
  }

  50% {
    transform: scale(1);
  }

  100% {
    transform: scale(0);
  }
}