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                <div class="pn-ProductNav_Wrapper">
<nav id="pnProductNav" class="pn-ProductNav">
    <div id="pnProductNavContents" class="pn-ProductNav_Contents">
        <a href="#" class="pn-ProductNav_Link" aria-selected="true">Chairs</a>
        <a href="#" class="pn-ProductNav_Link">Tables</a>
        <a href="#" class="pn-ProductNav_Link">Cookware</a>
        <a href="#" class="pn-ProductNav_Link">Beds</a>
        <a href="#" class="pn-ProductNav_Link">Desks</a>
        <a href="#" class="pn-ProductNav_Link">Flooring</a>
        <a href="#" class="pn-ProductNav_Link">Lighting</a>
        <a href="#" class="pn-ProductNav_Link">Mattresses</a>
        <a href="#" class="pn-ProductNav_Link">Solar Panels</a>
        <a href="#" class="pn-ProductNav_Link">Bookcases</a>
        <a href="#" class="pn-ProductNav_Link">Mirrors</a>
        <a href="#" class="pn-ProductNav_Link">Rugs</a>  
        <a href="#" class="pn-ProductNav_Link">Curtains &amp; Blinds</a>  
        <a href="#" class="pn-ProductNav_Link">Frames &amp; Pictures</a>  
        <a href="#" class="pn-ProductNav_Link">Wardrobes</a>  
        <a href="#" class="pn-ProductNav_Link">Storage</a>  
        <a href="#" class="pn-ProductNav_Link">Decoration</a>  
        <a href="#" class="pn-ProductNav_Link">Appliances</a>
		 <a href="#" class="pn-ProductNav_Link">Racks</a>
        <a href="#" class="pn-ProductNav_Link">Worktops</a>
	<button class="pn-Advancer pn-Advancer_Left" type="button">
		<svg class="pn-Advancer_Icon" xmlns="" viewBox="0 0 551 1024"><path d="M445.44 38.183L-2.53 512l447.97 473.817 85.857-81.173-409.6-433.23v81.172l409.6-433.23L445.44 38.18z"/></svg>
	<button class="pn-Advancer pn-Advancer_Right" type="button">
		<svg class="pn-Advancer_Icon" xmlns="" viewBox="0 0 551 1024"><path d="M105.56 985.817L553.53 512 105.56 38.183l-85.857 81.173 409.6 433.23v-81.172l-409.6 433.23 85.856 81.174z"/></svg>


                .pn-ProductNav_Wrapper {
	position: relative;
	padding: 0 11px;

.pn-ProductNav {
    /* Make this scrollable when needed */
    overflow-x: auto;
    /* We don't want vertical scrolling */
    overflow-y: hidden;
    /* For WebKit implementations, provide inertia scrolling */
    -webkit-overflow-scrolling: touch;
    /* We don't want internal inline elements to wrap */
    white-space: nowrap;
    /* If JS present, let's hide the default scrollbar */
    .js & {
        /* Make an auto-hiding scroller for the 3 people using a IE */
        -ms-overflow-style: -ms-autohiding-scrollbar;
        /* Remove the default scrollbar for WebKit implementations */
        &::-webkit-scrollbar {
            display: none;
	/* positioning context for advancers */
	position: relative;

.pn-ProductNav_Contents {
	float: left;

.pn-ProductNav_Link {
	text-decoration: none;
	color: #888;
	font-size: 1.2em;
	font-family: -apple-system, sans-serif;
	display: inline-flex;
	align-items: center;
	min-height: 44px;
	& + & {
		margin-left: 11px;
		padding-left: 11px;
		border-left: 1px solid #eee;
	&[aria-selected="true"] {
		color: #111;

.pn-Advancer {
	/* Reset the button */
	appearance: none;
	background: transparent;
	padding: 0;
	border: 0;
	&:focus {
		outline: 0;
	/* Now style it as needed */
	position: absolute;
	top: 0;
	bottom: 0;
	/* Set the buttons invisible by default */
	opacity: 0;
	transition: opacity .3s;

.pn-Advancer_Left {
	left: 0;
	[data-overflowing="both"] ~ &,
	[data-overflowing="left"] ~ & {
		opacity: 1;

.pn-Advancer_Right {
	right: 0;
	[data-overflowing="both"]  ~ &,
	[data-overflowing="right"] ~ & {
		opacity: 1;

.pn-Advancer_Icon {
	width: 20px;
	height: 44px;
	fill: #bbb;



var pnProductNav = document.getElementById("pnProductNav");
var pnProductNavContents = document.getElementById("pnProductNavContents");

pnProductNav.setAttribute("data-overflowing", determineOverflow(pnProductNavContents, pnProductNav));

// Handle the scroll of the horizontal container
var last_known_scroll_position = 0;
var ticking = false;

function doSomething(scroll_pos) {
    pnProductNav.setAttribute("data-overflowing", determineOverflow(pnProductNavContents, pnProductNav));

pnProductNav.addEventListener("scroll", function() {
    last_known_scroll_position = window.scrollY;
    if (!ticking) {
        window.requestAnimationFrame(function() {
            ticking = false;
    ticking = true;

function determineOverflow(content, container) {
    var containerMetrics = container.getBoundingClientRect();
    var containerMetricsRight = Math.floor(containerMetrics.right);
    var containerMetricsLeft = Math.floor(containerMetrics.left);
    var contentMetrics = content.getBoundingClientRect();
    var contentMetricsRight = Math.floor(contentMetrics.right);
    var contentMetricsLeft = Math.floor(contentMetrics.left);
	 if (containerMetricsLeft > contentMetricsLeft && containerMetricsRight < contentMetricsRight) {
        return "both";
    } else if (contentMetricsLeft < containerMetricsLeft) {
        return "left";
    } else if (contentMetricsRight > containerMetricsRight) {
        return "right";
    } else {
        return "none";