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HTML

              
                <h1 id="elem" class="animated" hidden>Animate</h1>

<button class="show">Show</button> <button class="hide">Hide</button>
              
            
!

CSS

              
                
              
            
!

JS

              
                /*!
 * Apply a CSS animation to an element
 * (c) 2018 Chris Ferdinandi, MIT License, https://gomakethings.com
 * @param  {Node}    elem      The element to animate
 * @param  {String}  animation The type of animation to apply
 * @param  {Boolean} hide      If true, apply the [hidden] attribute after the animation is done
 */
var animate = function (elem, animation, hide) {

	// If there's no element or animation, do nothing
	if (!elem || !animation) return;

	// Remove the [hidden] attribute
	elem.removeAttribute('hidden');

	// Apply the animation
	elem.classList.add(animation);

	// Detect when the animation ends
	elem.addEventListener('animationend', function endAnimation (event) {

		// Remove the animation class
		elem.classList.remove(animation);

		// If the element should be hidden, hide it
		if (hide) {
			elem.setAttribute('hidden', 'true');
		}

		// Remove this event listener
		elem.removeEventListener('animationend', endAnimation, false);

	}, false);

};

var elem = document.querySelector('#elem');

document.addEventListener('click', function (event) {

	if (event.target.matches('.show')) {
		animate(elem, 'fadeInDown');
	}

	if (event.target.matches('.hide')) {
		animate(elem, 'fadeOutUp', true);
	}

}, false);
              
            
!
999px

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