how to create hover animation on a div - css

Question

I wanted to create a div which has a background image and a transparent background color over it with some text. When hover, the transparent background color should slide out towards the bottom of the div as shown in the image:
https://i.ibb.co/pJFPvFB/Screenshot-2019-03-26-Zeplin-Project.png
Left block is default. Right block is hover state.
I modified this snippet: https://www.w3schools.com/howto/tryit.asp?filename=tryhow_css_image_overlay_fade
I modified the provided style to:
<style>
.container {
position: relative;
width: 50%;
}
.image {
display: block;
width: 100%;
height: auto;
}
.overlay {
position: absolute;
top: 0;
bottom: 0;
left: 0;
right: 0;
height: 100%;
width: 100%;
opacity: 0;
transition: .5s ease;
background-color: #008CBA;
}
.container .overlay {
opacity: 0.75;
}
.container:hover .overlay {
opacity: 0;
}
.text {
color: white;
font-size: 20px;
position: absolute;
top: 50%;
left: 50%;
-webkit-transform: translate(-50%, -50%);
-ms-transform: translate(-50%, -50%);
transform: translate(-50%, -50%);
text-align: center;
}
</style>
Edited:
My Problem
I tried to achieve a simple slideout animation on my as shown in the image I provided. See this: https://i.ibb.co/pJFPvFB/Screenshot-2019-03-26-Zeplin-Project.png
I have tried something like this - https://www.w3schools.com/howto/tryit.asp?filename=tryhow_css_image_overlay_fade
I edited the css they provided to the css I provided above.
Please see the image I provided. I wanted to achieve that.

Answer 1

Try this.
.container {
position: relative;
width: 50%;
}
.image {
display: block;
width: 100%;
height: auto;
}
.overlay {
position: absolute;
bottom: 0;
left: 0;
right: 0;
height: 100%;
width: 100%;
transition: .5s ease;
background-color: #008CBA;
}
.container:hover .overlay {
transition: .5s ease;
height: 0;
}
.text {
color: white;
font-size: 20px;
position: absolute;
top: 50%;
left: 50%;
-webkit-transform: translate(-50%, -50%);
-ms-transform: translate(-50%, -50%);
transform: translate(-50%, -50%);
text-align: center;
}
<div class="container">
<img src="https://i.ibb.co/pJFPvFB/Screenshot-2019-03-26-Zeplin-Project.png" alt="Avatar" class="image">
<div class="overlay">
<div class="text">Hello World</div>
</div>
</div>
Hope this code may help you.

Answer 2

Hi hope this is what you are looking for
Try this fiddle
.container:hover .overlay {
animation-name: slideDown;
-webkit-animation-name: slideDown;
animation-duration: 1s;
-webkit-animation-duration: 1s;
animation-timing-function: ease;
-webkit-animation-timing-function: ease;
opacity: 1 !important;
}

Answer 3

hope this is what you are looking
.box {
width: 200px; height: 100px;
background-size: 100% 200%;
background-image: linear-gradient(to bottom, red 50%, black 50%);
-webkit-transition: background-position 1s;
-moz-transition: background-position 1s;
transition: background-position 1s;}
http://jsfiddle.net/jxgrtmvy