Wrzucę może komuś się przyda. Powyższy efekt z wykorzystaniem samego CSS, codepen.io
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
body {
height: 100vh;
display: flex;
align-items: center;
justify-content: center;
}
.card {
width: 250px;
height: 300px;
overflow: hidden;
position: relative;
background-color: #000000;
}
.card img {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
}
.cover {
position: absolute;
bottom: 0;
left: 0;
height: 0;
transition: height 1s ease-in-out;
color: #D0D0D0;
background-color: #000000;
}
label {
position: absolute;
bottom: 20px;
left: calc(50% - 20px);
display: block;
width: 0;
height: 0;
border-left: 20px solid transparent;
border-right: 20px solid transparent;
border-bottom: 20px solid #D0D0D0;
z-index: 999;
transition: all 1s linear;
}
#triangle {
visibility: hidden;
}
#triangle:checked ~ .cover{
height: 100%;
}
#triangle:checked ~ label {
transform: rotate(180deg);
}
</style>
</head>
<body>
<div class="card">
<img src="html5.png" alt="">
<input type="checkbox" id="triangle">
<label for="triangle"></label>
<div class="cover">
Lorem ipsum dolor sit amet, consectetur adipisicing elit. Dolores mollitia aliquid et molestias nesciunt quae, exercitationem totam cum commodi eaque! Reprehenderit quibusdam, error accusantium eveniet veritatis nesciunt voluptatibus dolor cupiditate.
</div>
</div>
</body>
</html>