Many thanks Steven much appreciated.

Gallery opens fine in chrome and IE but shrinks in height to about one quarter in Firefox. I'm not a programmer but can find my way around HTML juist, the website I'm trying to update is very old and uses frames, the gallery is opening in a nested frame. Here is a copy of my page minus all of the menus and information. I'm using the default installation cade. Do I need to modify anything else apart from thr width and height?

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Title</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>Juicebox Gallery</title>
    <meta charset="utf-8" />
    <meta name="viewport" id="jb-viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1, maximum-scale=1, user-scalable=0" />
    <meta name="description" content="" />

    <!-- START OPEN GRAPH TAGS-->
    <meta property="og:title" content="Juicebox Gallery" />
    <meta property="og:type" content="website" />
    <meta property="og:url" content="" />
    <meta property="og:image" content="" />
    <meta property="og:description" content="" />
    <!-- END OPEN GRAPH TAGS-->

    <style type="text/css">
    body {
        margin: 0px;
    }
    </style>
</head>
<body>

                <!--START JUICEBOX EMBED-->

                <script src="jbcore/juicebox.js"></script>
<script>
new
                juicebox({
containerId: "juicebox-container",
galleryWidth:
                "250%",
galleryHeight: "100%",
backgroundColor:
                "rgba(34,34,34,1)"
});
</script>
<div id="juicebox-container"></div>

                <!--END JUICEBOX EMBED-->
                                   
                       
</body>
</html>