<button></button>
body {
	display: flex;
	justify-content: center;
	margin: 0;
	height: 100vh;
  background: linear-gradient(#f8f8f8, #d9d9d9);
}

button {
	align-self: center;
	border: solid .375em;
	border-image: linear-gradient(#fdfdfd, #c4c4c4) 1;
	width: 2.25em; height: 2.25em;
	box-shadow: 0 .375em .5em -.125em #808080;
	background: linear-gradient(#c5c5c5, #efefef);
	font-size: 1.5em;
	cursor: pointer;
	
	&:active { transform: translateY(1px); }
}
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