JSFiddle - React, Tailwind, and code Playground
HTML
<div class="canvas">
<div class="a"></div>
<div class="b"></div>
</div>
CSS
* {
margin: 0;
padding: 0;
}
.canvas {
width: 400px;
height: 300px;
background: #ff00ff;
position: relative;
display: flex;
justify-content: center;
align-content: center;
overflow: hidden;
}
.a, .b {
width: 100px;
height: 150px;
background: #ff0000;
}
.a {
box-shadow: 230px -250px 0 0 #000000;
width: 228px;
margin-left: -200px;
margin-top: 200px;
border-radius: 100vh;
}
.b {
height: 200px;
box-shadow: 100px 0 0 0 #000000;
margin-left: -100px;
margin-top: 50px;
}