css实现图片边缘模糊效果

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      * {
        margin: 0;
      }
      html {
        height: 100%;
      }
      body {
        height: 100%;
      }
      .avatar {
        width: 30%;
        height: 30%;
        border-radius: 200px;
        overflow: hidden;
        position: relative;
      }
      .avatar::after {
        /* 【主要代码】 */
        position: absolute;
        content: '';
        width: 100%;
        height: 100%;
        top: 0;
        left: 0;
        border-radius: 200px; /* 避免四个角没有阴影 */
        box-shadow: 0 0 50px 30px #fff inset; /* 【主要代码】 */
      }
      img {
        width: 100%;
        height: 100%;
      }
    </style>
  </head>
  <body>
    <div class="avatar">
      <img src="https://images.dog.ceo/breeds/pembroke/n02113023_6519.jpg" />
    </div>
  </body>
</html>