Here is a CSS code snippet to help you transition an image to Black and White on mouse hover.
Here is the full code
- The Black and White effect is achieved with the `grayscale` value for the [filter](https://developer.mozilla.org/en/docs/Web/CSS/filter) property. `grayscale(100%)` corresponds to Black and White and `grayscale(0%)` corresponds to full colors. The `-webkit-filter` prefix is [necessary for that property](http://shouldiprefix.com/#filters).
- The smooth animation is achieved with the [transition](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Transitions/Using_CSS_transitions) property.