<n-image
    width=98%
    mt-3
    src="https://example.com/ipfs/QmQKptGbRRziEjxxxxxx" 
    rounded-2 alt="AIJoe Meme"
 /> 
 //width=98% 可以使得图片自适应大小

<div class="contentimg">
  <img
    width=98%
    mt-3
    :src="takeImage(item.body)"
    rounded-2
  /> 
</div> 
<style>
.contentimg {
  width: 98%;
  height: 28rem;
  overflow: hidden;
  margin: auto;
} 
.contentimg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
</style>