How do I create a circle or square with just CSS - with a hollow center?

Question

It should just basically be an outline of the square or circle - that I can style accordingly (i.e. change the color to whatever I want, change the thickness of the border,

Answer 1

Try This

div.circle {
  -moz-border-radius: 50px/50px;
  -webkit-border-radius: 50px 50px;
  border-radius: 50px/50px;
  border: solid 21px #f00;
  width: 50px;
  height: 50px;
}

div.square {
  border: solid 21px #f0f;
  width: 50px;
  height: 50px;
}

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