是否可以将框阴影自定义为图像后面的三角形？

<style>
  .box {
    position: relative;
    width: 200px;
    height: 200px;
    background-color: #fff;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
  }

  .box::before {
    content: "";
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 0;
    border-left: 10px solid transparent;
    border-right: 10px solid transparent;
    border-top: 10px solid rgba(0, 0, 0, 0.5);
  }
</style>

<div class="box"></div>