my.css

background: linear-gradient(182deg, #0e5a71, #f7951e);
background-size: 400% 400%;
-webkit-animation: AnimationName 2s ease infinite;
-moz-animation: AnimationName 2s ease infinite;
-o-animation: AnimationName 2s ease infinite;
animation: AnimationName 2s ease infinite;
@-webkit-keyframes AnimationName {
    0%{background-position:52% 0%}
    50%{background-position:49% 100%}
    100%{background-position:52% 0%}

wpsmith

<?php

add_action( 'wp_enqueue_scripts', 'wps_load_scripts' );
/**
* Enqueue Isotope
* For commercially developed child themes, you must obtain a license
* from isotope.metafizzy.co for approx. $25.
*
* @author Travis Smith
* @link http://wpsmith.net