先上图 看效果
<img src="https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1603366090530&di=c577848925d530d810551eda33d2d57e&imgtype=0&src=http%3A%2F%2Fpic13.nipic.com%2F20110418%2F1039568_043023301140_2.jpg" /> <img class="img" src="https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1603366090530&di=c577848925d530d810551eda33d2d57e&imgtype=0&src=http%3A%2F%2Fpic13.nipic.com%2F20110418%2F1039568_043023301140_2.jpg" /> img { width: 400px; height: 400px; } .img { width: 400px; height: 400px; -webkit-filter: grayscale(100%); -moz-filter: grayscale(100%); -ms-filter: grayscale(100%); -o-filter: grayscale(100%); filter: grayscale(100%); filter: gray; }