Odoo

<div></div>
<div></div>
<div></div>
<div></div>
<style>
  body {
    background: #191919;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 2px;
  }
  div {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 20px solid #714b67;
    translate: 0 12px;
  }

  div:not(:first-child) {
    border-color: #8f8f8f;
  }

  div:nth-child(2)::after {
    content: '';
    position: absolute;
    top: -40px;
    left: 40px;
    width: 20px;
    height: 60px;
    background: #8f8f8f;
    border-radius: 50px 50px 0 0;
  }
</style>