1. paste this code before </style>
img {-webkit-transition: opacity 0.8s linear;opacity: 0.80;-webkit-filter:grayscale(100%);}
img:hover {-webkit-transition: opacity 0.8s linear;opacity: 1;-webkit-filter:none;}
2. preview > save
img {-webkit-transition: opacity 0.8s linear;opacity: 0.80;-webkit-filter:grayscale(100%);}
img:hover {-webkit-transition: opacity 0.8s linear;opacity: 1;-webkit-filter:none;}