Debounce

/**
 * Debounce functions for better performance.
 *
 * @source Chris Ferdinandi, https://gomakethings.com
 * @param  {Function} fn The function to debounce
 */
function debounce (fn) {

    // Setup a timer
    let timeout;

    // Return a function to run debounced
    return function () {

        // Setup the arguments
        let context = this;
        let args = arguments;

        // If there's a timer, cancel it
        if (timeout) {
            window.cancelAnimationFrame(timeout);
        }

        // Setup the new requestAnimationFrame()
        timeout = window.requestAnimationFrame(function () {
            fn.apply(context, args);
        });
    };
}