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console 命令行工具 X clear

                    
>
console
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <title>Document</title>
</head>
<body>
  <div id="box"></div>
</body>
</html>
* {
  margin: 0;
  padding: 0;
} 
div {
  height: 200px;
  width: 200px;
  margin-left: 0;
  background-color: red;
  animation: move 4s infinite;
}

@keyframes move {
  from {
    margin-left: 0;
  }
  50% {
    margin-left: 400px;
  }
  to {
    margin-left: 0;
  }
}