Animation CSS3: display + opacity

Question

I have got a problem with a CSS3 animation.

.child {
    opacity: 0;
    display: none;

    -webkit-transition: opacity 0.5s ease-in-out;
    -moz-transition: opacity 0.5s ease-in-out;
    transition: opacity 0.5s ease-in-out;
}

.parent:hover .child {
    opacity: 0.9;
    display: block;
}

This code only works if I remove the change of display.

I want to change the display just after the hover but the opacity should be changed using the transition.

Answer 1

You can do with CSS animations:

0% display:none ; opacity: 0;
1% display: block ; opacity: 0;
100% display: block ; opacity: 1;

Answer 2

HOW TO ANIMATE OPACITY WITH CSS:
this is my code:
the CSS code

.item {   
    height:200px;
    width:200px;
    background:red;
    opacity:0;
    transition: opacity 1s ease-in-out;
}

.item:hover {
    opacity: 1;
}
code {
    background: linear-gradient(to right,#fce4ed,#ffe8cc);
}

<div class="item">

</div>
<p><code> move mouse over top of this text</code></p>

or check this demo file

function vote(){
var vote = getElementById("yourOpinion")
if(this.workWithYou):
vote += 1 };
lol

Answer 3

To have animation on both ways onHoverIn/Out I did this solution. Hope it will help to someone

@keyframes fadeOutFromBlock {
  0% {
    position: relative;
    opacity: 1;
    transform: translateX(0);
  }

  90% {
    position: relative;
    opacity: 0;
    transform: translateX(0);
  }

  100% {
    position: absolute;
    opacity: 0;
    transform: translateX(-999px);
  }
}

@keyframes fadeInFromNone {
  0% {
    position: absolute;
    opacity: 0;
    transform: translateX(-999px);
  }

  1% {
    position: relative;
    opacity: 0;
    transform: translateX(0);
  }

  100% {
    position: relative;
    opacity: 1;
    transform: translateX(0);
  }
}

.drafts-content {
  position: relative;
  opacity: 1;
  transform: translateX(0);
  animation: fadeInFromNone 1s ease-in;
  will-change: opacity, transform;

  &.hide-drafts {
    position: absolute;
    opacity: 0;
    transform: translateX(-999px);
    animation: fadeOutFromBlock 0.5s ease-out;
    will-change: opacity, transform;
  }
}