Я только что изменил пару вещей в вашей HTML разметке и добавил дополнительный CSS код
<div class="container">
<h2 style="margin-bottom: 3rem; margin-top: 1rem;">Align right in Bootstrap 4</h2>
<div class="card mb-4" style="max-width: 300px; min-width: 300px" data-clickable="true">
<div class="card-inner">
<img src="https://via.placeholder.com/1420x1933" class="card-img" alt="...">
<div class="card-img-overlay">
<div class="cardContent">
<h5 class="card-title">Card Title</h5>
<p class="card-text info">This is a wider card with supporting text below as a natural lead-in to additional content. This content is a little bit longer.</p>
</div>
<div class="alignToEnd">
<p class="smallinfo"><b>1: </b>John</p>
<p class="smallinfo"><b>2: </b>Smith</p>
<p class="smallinfo"><b>3: </b>2008</p>
</div>
</div>
</div>
</div>
</div>
<style>
.card{
width: 300px;
min-height: 408px;
-webkit-perspective: 1000px;
perspective: 1000px;
border: 0px;
background-color: #fff;
-webkit-box-shadow: 0 5px 10px rgba(0, 0, 0, 0.0), 0 15px 40px rgba(0, 0, 0, 0.0);
box-shadow: 0 5px 10px rgba(0, 0, 0, 0.0), 0 15px 40px rgba(0, 0, 0, 0.0);
}
.card-inner {
position: relative;
width: 100%;
height: 100%;
text-align: left;
-webkit-transition: -webkit-transform 0.6s;
transition: -webkit-transform 0.6s;
-o-transition: transform 0.6s;
transition: transform 0.6s;
transition: transform 0.6s, -webkit-transform 0.6s;
-webkit-transform-style: preserve-3d;
transform-style: preserve-3d;
}
.card-title {
text-align: center;
font-size: 1.7rem;
}
.info{
font-size: 0.9rem;
}
.isbn {
text-align: left;
}
.card.active .card-inner {
-webkit-transform: rotateY(180deg);
transform: rotateY(180deg);
}
.card img, .card-img-overlay {
position: absolute;
width: 100%;
height: 100%;
-webkit-backface-visibility: hidden;
backface-visibility: hidden;
top:0;left:0;right:0;
}
.card-img-overlay {
-webkit-transform: rotateY(180deg);
transform: rotateY(180deg);
background:#444c43;
color:white;
position:relative;
}
.cardContent {
padding-bottom:60px;
}
.alignToEnd {
position:absolute;
bottom:0;
left:0;
width:100%;
display:-webkit-box;
display:-ms-flexbox;
display:flex;
-webkit-box-align:center;
-ms-flex-align:center;
align-items:center;
-webkit-box-pack:center;
-ms-flex-pack:center;
justify-content:center;
}
.alignToEnd > * {
width: 100%;
dispaly:flex;
-webkit-box-align:center;
-ms-flex-align:center;
align-items:center;
-webkit-box-pack:center;
-ms-flex-pack:center;
justify-content:center;
text-align:center;
}
</style>