<a href="#" class="btn">Purchase Tickets</a>

* {
  box-sizing: border-box;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body,
html {
  width: 100%;
  height: 100%;
  background: #222;
}

.btn {
	font-family: 'Oswald', sans-serif;
	display: block;
	height: 40px;
	padding: 5px 30px;
	text-align: center;
	text-decoration: none;
	width: 190px;
	font-size: 13px;
	line-height: 2em;
	font-weight: normal;
	letter-spacing: 1px;
	text-transform: uppercase;
	transition: all .3s ease-in-out;
	position: absolute;
	top: 50%;
	left: 50%;
	transform: translate3D(-50%, -50%, 0);
  color: #fff;
  border: 2px solid #fff;

	&:before,
	&:after {
		width: 0%;
		height: 2px;
		position: absolute;
		background: #e5c100;
		transition: width .4s ease-in-out;
		content: " ";
	}

	&:before {
		left: 0;
		top: -2px;
	}

	&:after {
		bottom: -2px;
		right: 0;
	}

	&:hover {
		padding: 5px 25px 5px 35px;
		border-color: #e5c100;
    color: lighten(#e5c100, 50%);

		&:before,
		&:after {
			width: 100%;
		}
	}
}