Layered card

<div class="layered-card">
...
</div>
.layered-card {
position: relative;
}
.layered-card::before {
background: rgba(0, 0, 0, 0.3);
content: '';
/* Position */
top: 0;
left: 0;
position: absolute;
transform: translate(1rem, 1rem);
/* Size */
height: 100%;
width: 100%;
/* Display under the main content */
z-index: -1;
}

See also

Card

Stacked cards

Three dimensions card