border radius tricks

by Soviut

HTML

<div class="circle"></div>

CSS

* {
  box-sizing: border-box;
}

.circle {
  display: block;
  width: 300px;
  height: 300px;
  
  background: cornflowerblue;
  border-radius: 50%;
  border: black solid;
  border-width: 150px 0 0 0;
}