Hola el estilo que utiliza es el siguiente:
		<style>
	#container { margin-top: 0; }
	.home-header,
	.module .inner-back h2 .line {
		background: linear-gradient(270deg, #fd03d2, #fd4703, #fded03, #03f0fd);
		background-size: 400%; 
		-webkit-animation: gradFade 20s ease infinite;
		-moz-animation: gradFade 20s ease infinite;
		animation: gradFade 20s ease infinite;
	}
	.work-header h1 .line {
		background: linear-gradient(
			270deg, 
			#fd03d2, #fd4703, #fded03, #03f0fd		);
		background-size: 400%; 
		-webkit-animation: gradFade 20s ease infinite;
		-moz-animation: gradFade 20s ease infinite;
		animation: gradFade 20s ease infinite;
	}
	.home-bkg-image {
		background-image: url(
http://m-goldstein.com/wp-content/up...8/mg-new.jpg);
		opacity: 0.19;
	} 
	.pageload-overlay::before {
		background-image: linear-gradient(270deg, #fd03d2, #fd4703, #fded03, #03f0fd);
		background-size: 400%;
		-webkit-animation: gradFade 10s ease infinite;
		-moz-animation: gradFade 10s ease infinite;
		animation: gradFade 10s ease infinite;
	}
	</style> 
Este es el HTML:
<header class="home-header h100">
				<div class="home-bkg-image"></div>
				<div class="inner-home-header">
					<div class="home-header-content">
						<div class="move-wrap" id="elem">
							<h1 style="transform: translate(-1.0125px, 8.72958px);">Mark Goldstein</h1>
							<p style="transform: translate(-1.0125px, 8.72958px);">Art Direction + Design</p>
							<div class="line-wrap" style="transform: translate(1.0125px, -8.72958px);">
								<span class="line"></span>
							</div>
						</div>
					</div>
					<span class="icon downarrow"></span>
				</div>
			</header> 
No sé si usará un js aparte. 
Un saludo