.gray {-webkit-filter: grayscale(100%); -moz-filter: grayscale(100%); -ms-filter: grayscale(100%); -o-filter: grayscale(100%); filter: grayscale(100%); filter: gray; }
灰色滤镜，网页灰色代码
原文：http://www.cnblogs.com/ziye/p/4560308.html
