<div class="borderBox"><div class="copy">Under Construction</div></div>
* {
	box-sizing: border-box;
}
body,html {
	padding:0px;
	margin:0px;
}
.borderBox {
	background-color: #ffc600;
	border: 30px solid transparent;
	border-image: url('https://lounge07.com/images/construction_b.png') 100 100 round;
	width: 100%;
	height: 300px;
	color: #000;
	text-align: center;
	font-family: Helvetica, Arial, sans-serif;
	animation-duration: 2s;
	animation-name: changeColor;
	animation-iteration-count: infinite;
}
.copy {
	height: 240px;
	line-height: 240px;
	font-size: 3em;
}

@keyframes changeColor {
	from {
		background-color: #ffc600;
	}
	25% {
		border-image: url('https://lounge07.com/images/construction_y.png') 100 100 round;
	}
	50% {
		background-color: #000;
		color: #ffc600;
		border-image: url('https://lounge07.com/images/construction_b.png') 100 100 round;
	}
	75% {
		border-image: url('https://lounge07.com/images/construction_y.png') 100 100 round;
	}
	to {
		background-color: #ffc600;
	}
}

External CSS

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External JavaScript

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