CSS how to make an element fade in and then fade out?

Question

I can make an element with an opacity of zero fade in by changing its class to .elementToFadeInAndOut with the following css:

.elementToFadeInAndOut {
    op         


        

Answer 1

If you need a single fadeIn/Out without an explicit user action (like a mouseover/mouseout) you may use a CSS3 animation: http://codepen.io/anon/pen/bdEpwW

.elementToFadeInAndOut {

    animation: fadeinout 4s linear 1 forwards;
}



@keyframes fadeinout {
  0% { opacity: 0; }
  50% { opacity: 1; }
  100% { opacity: 0; }
}

By setting animation-fill-mode: forwards the animation will retain its last keyframe

By setting animation-iteration-count: 1 the animation will run just once (change this value if you need to repeat the effect more than once)