JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
  <li class="active"></li>
  <li></li>
  <li></li>
  <li></li>
</ul>

CSS

ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
}

ul li {
  flex: 0 0 6px;
  width: 6px;
  height: 6px;
  margin: 0 3px;
  background-color: #000;
  border-radius: 100%;
  position: relative;
}

.active:before {
  content: '';
  position: absolute;
  top: -3px;
  left: -3px;
  right: -3px;
  bottom: -3px;
  border: 1px solid #000;
  border-radius: 100%;
}