JSFiddle - React, Tailwind, and code Playground

HTML

<main>
    <img src="http://placehold.it/350x150"/>
    <div class="shadow"></div>
</main>

CSS

body {
    background-color: #BBB;
}
main {
    position: absolute;
    bottom: 0;
    right: 0;
    width: 90%;
    height: 90%;
    background-color: #FFFFFF;
    border-radius: 20px;
}

main img {    
    border-radius: 20px;
}

.shadow {
    position: absolute;
    width: 100%;
    height: 100%;
    box-shadow: inset 3px 3px 10px 0 #000000;
    border-radius: 20px;
    top: 0;
    left: 0;
}