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console 命令行工具 X clear

                    
>
console
<div class="container">
    <div class="progress-bar"></div>
</div>
.progress-bar {
  background-color: #fff;
  height: 4px;
  width: 100%;
  animation: grow 10s linear infinite;
  transform-origin: left;
}

@keyframes grow {
  0% {
    transform: scaleX(0);
  }
}