Auto fade out and fade In on hover animation - css

Question

This is auto fade out after hover css animation
I'm trying to show a notification on video play button. The button click actually clicked for video play. I want to show a div with its content with the play icon. However, I would like to fade out the play icon, lets say after 5 seconds . I would like to achieve it using CSS. Below is my attempt. Please inform me if better solution here.
Here is the live Demo
body {
font-size: 50%;
font-style: Arial;
}
.animation-box {
width: 75%;
height: 27.5rem;
background-color: blue;
margin: 0 auto;
overflow: hidden;
position: relative;
}
.animation-container {
width: 1000rem;
height: 30rem;
}
.first-text {
font-size: 4rem;
position: absolute;
left: 2.5rem;
top: 5rem;
color: white;
-webkit-animation: fadeOut 2s forwards;
animation: fadeOut 2s forwards;
-webkit-animation-delay: 5s;
animation-delay: 5s;
}
.first-text:hover {
-webkit-animation: fadeIn 0s forwards;
animation: fadeIn 0s forwards;
-webkit-animation-delay: 0.5s;
animation-delay: 0.5s;
}
#-webkit-keyframes fadeIn {
from {opacity: 0;}
to {opacity: 1;}
}
#keyframes fadeIn {
from {opacity: 0;}
to {opacity: 1;}
}
#-webkit-keyframes fadeOut {
from {opacity: 1;}
to {opacity: 0;}
}
#keyframes fadeOut {
from {opacity: 1;}
to {opacity: 0;}
}
<section class="animation-box">
<h1 class="first-text">This is auto fade out after hover </h1>
</section>

Answer 1

You can achieve this with just transition :
body {
font-size: 50%;
font-style: Arial;
}
.animation-box {
width: 75%;
height: 27.5rem;
background-color: blue;
margin: 0 auto;
overflow: hidden;
position: relative;
}
h1{
opacity:0;
transition: opacity 250ms 5s ease;
}
.animation-box:hover h1{
opacity:1;
transition-delay: 250ms;
}
<section class="animation-box">
<h1 class="first-text">This is auto fade ou1t after hover </h1>
</section>

Answer 2

.Class {
transition: all 0.5s;
color: #ff0;
margin: 50px;
font-size: 28px;
cursor: pointer;
}
.Class:hover {
color: #00f;
}
<p class="Class"> This is me </p>

Answer 3

Use transition:0.5s ease with opacity:0
<section class="animation-box">
<h1 class="first-text">This is auto fade ou1t after hover </h1>
</section>
.animation-box{
transition: 0.5s ease;
}
.animation-box:hover{
opacity:0;
transition: 0.5s ease;
}