点击时添加 "波纹" 效果 - 在线编辑器

          <!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <style>
    .button {
      position: relative;
      background-color: #4CAF50;
      border: none;
      font-size: 28px;
      color: #FFFFFF;
      padding: 20px;
      width: 200px;
      text-align: center;
      -webkit-transition-duration: 0.4s;
      /* Safari */
      transition-duration: 0.4s;
      text-decoration: none;
      overflow: hidden;
      cursor: pointer;
    }

    .button:after {
      content: "";
      background: #90EE90;
      display: block;
      position: absolute;
      padding-top: 300%;
      padding-left: 350%;
      margin-left: -20px!important;
      margin-top: -120%;
      opacity: 0;
      transition: all 0.8s
    }

    .button:active:after {
      padding: 0;
      margin: 0;
      opacity: 1;
      transition: 0s
    }
  </style>
</head>
<body>

  <h2>按钮动画 - 波纹效果</h2>

  <button class="button">Click Me</button>

</body>
</html>
        