<button></button>
$d-btn: 27em; /* control diameter */
$bw: 1.5em; /* border-width */

body {
	overflow: hidden;
	margin: 0;
	display: flex;
	justify-content: center;
	height: 100vh;
	background: #252525;
}

button {
	align-self: center;
	box-sizing: border-box;
	border: solid $bw transparent;
	padding: 1.5em;
	width: $d-btn; height: $d-btn;
	border-radius: 50%;
}
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