Untitled

<div class="container">
  <div class="column"></div>
  <div class="half-circle"></div>
</div>

<style>
  body {
    background: #FFF1F1;
  }
  .container {
    width: 100vw;
    height: 100vh;
    margin: 0;
    display: flex;
    gap: 50px;                 
    padding-top: 52px;
  }

  .column {
    width: 50px;
    height: 180px;
    margin-left: 50px;
    background: #F2A3AB;
    box-shadow: 230px 0 #F2A3AB;
  }

  .half-circle {
    height: 80px;
    width: 39px;
    border: 50px solid #84B9C7;
    border-radius: 180px 0 0 180px;
    border-right: 0;
  }
</style>