I am using this css-only lightbox:
https://www.thecssninja.com/demo/futurebox/#close
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<meta name="author" content="The CSS Ninja" />
<meta name="keywords" content="CSS, CSS3, CSS pseudo selectors, Futurebox" />
<meta name="description" content="Futurebox, lightbox without the javascript" />
<meta name="robots" content="all" />
<meta name="copyright" content="The CSS Ninja" />
<link rel="stylesheet" type="text/css" href="https://www.thecssninja.com/demo/futurebox/_styles.css" media="screen" />
<title>Futurebox, lightbox without the javascript | The CSS Ninja</title>
</head>
<body>
<div id="cssninja">
<p><a href="http://www.thecssninja.com/xhtml/futurebox">Example from the [CSS] Ninja</a></p>
</div>
<ul>
<li><a href="#futurebox_img1"><img src="gr_ninja-attack_med.gif" width="100" height="102" alt="The CSS Ninja" id="futurebox01" /></a></li>
<li><a href="#futurebox_img2"><img src="gr_ninja-attack_med.gif" width="100" height="102" alt="The CSS Ninja" id="futurebox01" /></a></li>
<li><a href="#futurebox_img3"><img src="gr_ninja-attack_med.gif" width="100" height="102" alt="The CSS Ninja" id="futurebox01" /></a></li>
<li><a href="#futurebox_img4"><img src="gr_ninja-attack_med.gif" width="100" height="102" alt="The CSS Ninja" id="futurebox01" /></a></li>
<li><a href="#futurebox_img5"><img src="gr_ninja-attack_med.gif" width="100" height="102" alt="The CSS Ninja" id="futurebox01" /></a></li>
</ul>
<div class="overlay" id="futurebox_img1">
<a href="#close" title="Close future box"><img src="gr_cssninja_lrg.png" alt="The Css Ninja" width="469" height="500" /></a>
</div>
<div class="overlay" id="futurebox_img2">
<a href="#close" title="Close future box"><img src="gr_cssninja_lrg2.png" alt="The Css Ninja" width="469" height="500" /></a>
</div>
<div class="overlay" id="futurebox_img3">
<a href="#close" title="Close future box"><img src="gr_cssninja_lrg3.png" alt="The Css Ninja" width="469" height="500" /></a>
</div>
<div class="overlay" id="futurebox_img4">
<a href="#close" title="Close future box"><img src="gr_cssninja_lrg4.png" alt="The Css Ninja" width="469" height="500" /></a>
</div>
<div class="overlay" id="futurebox_img5">
<a href="#close" title="Close future box"><img src="gr_cssninja_lrg5.png" alt="The Css Ninja" width="469" height="500" /></a>
</div>
<!-- Google analytics -->
<script type="text/javascript">
var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));
</script>
<script type="text/javascript">
var pageTracker = _gat._getTracker("UA-4638292-1");
pageTracker._initData();
pageTracker._trackPageview();
</script>
</body>
</html>
My problem is, when I use this lightbox inside an iframe the lightbox is opening only in the middle of that iframe. You can see what I mean here in jsfiddle:
https://jsfiddle.net/sqvz2ahp/
Is it possible that the lightbox is always in the center of the browser page, no matter if my code was implemented with an iframe?
The important thing is: I can only work with CSS not with javascript.