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                <!-- Lightbox usage markup -->
<link href=",100,400" rel="stylesheet" type="text/css" />
<h1>Mostly CSS Lightbox</h1>
<p>Supports images, youtube, and vimeo content.</p>

<!-- thumbnail image wrapped in a link -->
<a class="thumbnail" href="#img1" onclick="lightboxShow('img1'); return false;" style="background-image: url(;">image 1</a>

<a class="thumbnail" href="#img2" onclick="lightboxShow('img2'); return false;" style="background-image: url(;">image 2</a>

<a class="thumbnail" href="#img3" onclick="lightboxShow('img3'); return false;" style="background-image: url(;">image 3</a>


<a class="thumbnail" href="#img4" onclick="lightboxShow('img4'); return false;" style="background-image: url(;">image 4</a>

<a class="thumbnail" href="#img5" onclick="lightboxShow('img5'); return false;" style="background-image: url(;">image 5</a>

<a class="thumbnail" href="#img6" onclick="lightboxShow('img6'); return false;" style="background-image: url(;">image 6</a>

<!-- lightbox containers hidden with CSS -->
<a class="lightbox animate" href="#!" onclick="lightboxHide('img1'); return false;" id="img1">
	<img class="animate" src="" alt="image 1" /><span class="close"></span></a>

<a class="lightbox animate" href="#!" onclick="lightboxHide('img2'); return false;" id="img2">
	<img class="animate" src="" alt="image 2" /><span class="close"></span></a>

<a class="lightbox animate" href="#!" onclick="lightboxHide('img3'); return false;" id="img3">
	<img class="animate" src="" alt="image 3" /><span class="close"></span></a>

<a class="lightbox animate" href="#!" onclick="lightboxHide('img4'); return false;" id="img4">
	<img class="animate" src="" alt="image 4" /><span class="close"></span></a>

<a class="lightbox animate" href="#!" onclick="lightboxHide('img5'); return false;" id="img5">
	<img class="animate" src="" alt="image 5" /><span class="close"></span></a>

<a class="lightbox animate" href="#!" onclick="lightboxHide('img6'); return false;" id="img6">
	<img class="animate" src="" alt="image 6" /><span class="close"></span></a>


<!-- thumbnails wrapped in a link -->
<a class="thumbnail" href="#vid1" onclick="lightboxShow('vid1'); vid1.playVideo(); return false;" style="background-image: url(;">YouTube video</a>

<a class="thumbnail" href="#vid2" onclick="lightboxShow('vid2');; return false;" style="background-image: url(;">Vimeo video</a>

<a class="thumbnail" href="#vid3" onclick="lightboxShow('vid3');; return false;" style="background-image: url(;">Vimeo video</a>

<!-- lightbox containers hidden with CSS -->
<div class="lightbox animate" id="vid1">
	<a class="close" href="#!" onclick="lightboxHide('vid1'); vid1.pauseVideo(); return false;"></a>
	<iframe class="animate" src="" allowfullscreen onload="vid1=new YT.Player(this)"></iframe></div>

<div class="lightbox animate" id="vid2">
	<a class="close" href="#!" onclick="lightboxHide('vid2'); vid2.pause(); return false;"></a>
	<iframe class="animate" src="" width="100%" height="100%" allowfullscreen onload="vid2=new Vimeo.Player(this)"></iframe>

<div class="lightbox animate" id="vid3">
	<a class="close" href="#!" onclick="lightboxHide('vid3'); vid3.pause(); return false;"></a>
	<iframe class="animate" src="" allowfullscreen onload="vid3=new Vimeo.Player(this)"></iframe></div>


<p> While this uses only HTML and CSS for layout and animation, it <i>does</i> require Javascript to allow for automated play/pause when opening/closing the layer. In addition, this variation also uses Javascript to override default :target behaviour to set states. This stops the browser history from filling up with endless anchor links, but if javascript is disabled, the :target behaviour still works as expected.</p>

<p>YouTube and Vimeo API scripts are loaded in the header, while the iframes include onload actions to initialise the APIs, and the anchor elements include onclick actions for setting status.</p>

<h3>Known bugs:</h3>

<p>The YouTube API will not automatically restart a finished video until the second "play" commend. This means watching a video, letting it finish, then closing and re-opening the lightbox will not autoplay from the begining, but trying a second time will.</p>

<p>If the lightbox closing animation hasn't finished yet, clicks can sometimes catch the video in mid-scale, causing the media to start playing again (continuing while invisible) or activating other buttons. Speeding up the animation can help prevent this, or simply removing animation entirely (delete the "animation" class from the lightbox elements).</p>


                /*Eliminates padding, sets up document style */

body, html {
	padding: 0;
	margin: 0;
	text-align: center;
	font-family: 'Raleway', sans-serif;
	font-size: 18px;
	color: #888480;
	background-color: #202428;

p {
	width: 40%;
	min-width: 420px;
	max-width: 800px;
	margin: 30px auto;
	line-height: 1.3em;

/* Removes browser highlight outlines for all links */

a {
	color: #fff;
	text-decoration: none;

a:focus {
	outline: none;

/* Styles the thumbnail */

.thumbnail {
	/* make link text transparent, but retain content for accessibility */
	color: rgba(255, 255, 225, 0);
	/* positioning and styling of thumbnails */
	position: initial;
	display: inline-block;
	width: 240px;
	height: 135px;
	background-position: center center;
	background-size: cover;
	border: 2px solid white;
	margin: 20px;
	border-radius: 10px;

/* Styles the lightbox elements, removes it from sight and defines animation curves */

.lightbox {
	position: fixed;
	display: block;
	top: 0;
	bottom: 0;
	left: 0;
	right: 0;
	background: #000;
	background: rgba(0, 0, 0, .75);
	visibility: hidden;
	opacity: 0;
	/*	z-index: 999;*/

.close {
	display: block;
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;

.animate {
	-webkit-transition: .15s ease-in-out;
	-moz-transition: .15s ease-in-out;
	-ms-transition: .15s ease-in-out;
	-o-transition: .15s ease-in-out;
	transition: .15s ease-in-out;

/* Styles the lightbox content, centers it vertically and horizontally, adds the zoom-in transition and makes it responsive using a combination of margin and absolute positioning */

.lightbox img {
	position: absolute;
	display: block;
	margin: auto;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	max-width: 30%;
	max-height: 30%;
	border: 2px solid white;
	/*	box-sizing: border-box;*/

.lightbox iframe {
	position: absolute;
	display: block;
	margin: auto;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	width: 30vw;
	/* 30% of viewport width */
	height: 16.875vw;
	/* 9/16 * 30 = 16.875 */
	max-height: 30vh;
	/* 30% of viewport height */
	max-width: 53.333333333vh;
	/* 16/9 * 90 = 53.333333333 */
	border: 2px solid white;
	/*	box-sizing: border-box;*/

/* Uses the :target pseudo-class to perform the animations upon clicking the .lightbox anchor */

.lightbox:target, .overlay {
	visibility: visible;
	opacity: 1;

.lightbox:target img, .overlay img {
	max-width: 90%;
	max-height: 90%;

.lightbox:target iframe, .overlay iframe {
	width: 90vw;
	/* 90% of viewport width */
	height: 50.625vw;
	/* (9/16) * 90 = 50.625 */
	max-height: 90vh;
	/* 90% of viewport height */
	max-width: 160vh;
	/* (16/9) * 90 = 160 */



                // ClassList approach taken from

function lightboxShow(id) {

function lightboxHide(id) {