-webkit-transition:background-image 0.6s ease-in;
-moz-transition:background-image 0.6s ease-in;
-o-transition:background-image 0.6s ease-in;
transition:background-image 0.6s ease-in;
After testing in Safari, Firefox, and Chrome, I found that only Firefox is not displaying the expected behavior. While some suggest that Firefox does not support this feature, I am exploring alternative methods to make it work in Firefox without resorting to creating a JavaScript-controlled animation specifically for Firefox.