一键置灰
.gray { -webkit-filter: grayscale(100%); -moz-filter: grayscale(100%); -ms-filter: grayscale(100%); -o-filter: grayscale(100%); filter: grayscale(100%); -webkit-filter: gray; filter: gray; -webkit-filter: progid:dximagetransform.microsoft.basicimage(grayscale=1); filter: progid:dximagetransform.microsoft.basicimage(grayscale=1); }