<div class="box"></div>
.box {
  width: 200px;
  aspect-ratio: 1;
  background: red;
  -webkit-mask: conic-gradient(from 22deg, #0003,#000);
          mask: conic-gradient(from 22deg, #0003,#000);
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-content: center;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.