CSS animations (part 1)

Our main navigation is now coming together, and our drop-down functionality is almost complete. One of the last finishing touches required for the dropdown is the CSS animation, to allow the drop-down menu to animate downward smoothly. Animations are a lot of fun, and modern browsers, including Chrome, Firefox, Opera, and browsers starting with IE10, support them. IE9 will still show a drop-down menu, but it will simply appear/disappear. An animation is very similar to a transition, but instead of simply animating a state change, we can animate static elements and use different animation properties and key frames to control the animation. We'll get more into this later. So here's what we're going to do in this section: We'll define the animation-name, animation-duration, and animation-timing-function inside the selector of the element...