原图：

模糊后的图片：

html:

<div class="bj"><div class="mengban"></div>
</div>

css:

.bj {width: 750rpx;height: 643rpx;background-image:url('https://onlinekc.a.hlidc.cn/uploads/20241023/9e552fc928cc9407336b1920024f14de.png');background-size: cover;background-position: center;background-repeat: no-repeat;.mengban {width: 100%;height: 100%;background-color: rgba(0, 0, 0, 0.1);backdrop-filter: blur(13px);//值越大越模糊（重要代码）}
}