<div class="donut">
<div class="rectangle"></div>
</div>
<style>
body {
display: grid;
place-items: center;
background: #6592cf;
}
.donut {
width: 100px;
height: 100px;
border-radius: 50%;
border: solid 50px #243d83;
position: relative;
}
.rectangle {
position: absolute;
width: 50px;
height: 100px;
background: #243d83;
inset: -50px;
box-shadow: 50px 0 #6592cf;
}
</style>
<a a><a b><style>*{background:#6592CF}a{position:fixed;top:50;left:100}[a]{width:100;height:100;border:50px solid#243D83;border-radius:50%}[b]{background:#243D83;width:50;height:100;box-shadow:50px 0#6592CF