diff --git a/README.rst b/README.rst
index 14c2644..0f223fd 100644
--- a/README.rst
+++ b/README.rst
@@ -1,7 +1,8 @@
 sphinx_galleria
 ###############
 
-Create image galleries with Sphinx.
+Create image galleries with Sphinx. No external JS
+dependency.
 
 Install
 ~~~~~~~
@@ -12,6 +13,11 @@ If you're using a virtualenv, just:
 
    pip install sphinx-galleria
 
+.. important::
+
+   Your webserver must deliver .mjs file with correct
+   content type (`application/javascript`).
+
 Using
 ~~~~~
 
@@ -23,24 +29,30 @@ Just use the galleria directive like this:
 .. code:: rst
 
    .. galleria:: imagefile1 imagefile2  images*.jpg
-      :galleria: (optional) Name of gallery
-      :description: (optional) A long description
-      :title: (optional) Title of image
-      :thumbsize: (optional) Image size (defaults to "100x100")
-      :transition: (optional, once) Transition for gallery
-      :theme: (optional, once) Theme name for galleria
-      :class: (optional, once) HTML class for gallery
+      :galleria: (optional) Name of gallery - node level
+      :alt: (optional) A long description - image level
+      :title: (optional) Title of image - image level
+      :thumbsize: (optional) Image size (defaults to "100x100") - image level
+      :width: Width of image (in pixel or percentage or with unit, default auto) - node level
+      :height: (optional) Height of image (in pixel or with unit) - node level
+      :align: Align to 'right', 'left' or 'center' (default to center) - node level
+      :hide_title: Flag - hide title under image (not in dialog) - image level
+      :hide_alt: Flag - hide alternative text under image - image level
+      :transition: (optional, once) Transition for gallery - image level
+      :class: (optional, once) HTML class for gallery - node level
 
-Title, thumbnail size and description are same for all
-images defined by the directive. If you need separated
-descriptions and titles, just use the directive several
-times with the same galleria name. In this case, theme
-html class and transition must be defined only in
-one directive.
+Image level options are same for all images defined by
+the directive. If you need separated descriptions and
+titles, just use the directive several times with the
+same galleria name. In this case, node level options
+must be defined only once.
 
 Thumbnail size is in "WIDTHxHEIGHT" format, resulting
 image keeps ratio.
 
+The first image of a gallery is displayed if javascript
+is not available on the browser.
+
 Licensing
 ~~~~~~~~~
 
diff --git a/setup.py b/setup.py
index 296d206..d53f634 100644
--- a/setup.py
+++ b/setup.py
@@ -17,7 +17,7 @@ setup(
     package_data={
         "sphinx_galleria": [
             "*.py",
-            "static/sphinxgalleria/*.js",
+            "static/sphinxgalleria/*.mjs",
             "static/sphinxgalleria/*.css",
         ]
     },
diff --git a/sphinx_galleria/__init__.py b/sphinx_galleria/__init__.py
index 15d91b6..68b378d 100644
--- a/sphinx_galleria/__init__.py
+++ b/sphinx_galleria/__init__.py
@@ -2,7 +2,7 @@
 # -*- coding: utf-8 -*-
 
 """
-Create image galleries with GalleriaJS
+Create image galleries
 """
 import os
 from typing import Dict, Any
@@ -39,8 +39,28 @@ def copy_images_files(app: Sphinx, env: BuildEnvironment) -> None:
             ensuredir(os.path.dirname(dest))
 
             with Image.open(original) as im:
-                im.thumbnail(thumbsize)
-                im.save(dest, "JPEG")
+                if im.size[0]/im.size[1] > thumbsize[0]/thumbsize[1]:
+                    out = im.resize((
+                        thumbsize[0],
+                        thumbsize[1]
+                    ), box=(
+                        (im.size[0]-thumbsize[1]*im.size[0]/thumbsize[0])//2,
+                        0,
+                        (im.size[0]+thumbsize[1]*im.size[0]/thumbsize[0])//2,
+                        im.size[1]
+                    ))
+                else:
+                    out = im.resize((
+                        thumbsize[0],
+                        thumbsize[1]
+                    ), box=(
+                        0,
+                        (im.size[1]-thumbsize[0]*im.size[1]/thumbsize[0])//2,
+                        im.size[0],
+                        (im.size[1]+thumbsize[0]*im.size[1]/thumbsize[0])//2,
+                    ))
+
+                out.save(dest, "JPEG")
 
 
 def install_static_files(app: Sphinx, env: BuildEnvironment) -> None:
@@ -69,12 +89,16 @@ def install_static_files(app: Sphinx, env: BuildEnvironment) -> None:
 
         copyfile(source_path, static_path)
 
-        if static.endswith('.js'):
-            app.add_js_file(os.path.join('sphinxgalleria', static))
-        elif static.endswith('.css'):
+        if static.endswith('.css'):
             app.add_css_file(os.path.join('sphinxgalleria', static))
 
 
+def init_directive(app: Sphinx, config) -> None:
+    if 'galleria_override_image' in config and \
+            config['galleria_override_image']:
+        app.add_directive('image', directive.GalleriaDirective)
+
+
 def setup(app: Sphinx) -> Dict[str, Any]:
     app.add_node(
         directive.galleria,
@@ -88,6 +112,8 @@ def setup(app: Sphinx) -> Dict[str, Any]:
     )
     app.add_directive('galleria', directive.GalleriaDirective)
     app.add_env_collector(collector.GalleriaCollector)
+    app.add_config_value('galleria_override_image', False, 'boolean')
     app.connect('env-updated', install_static_files)
     app.connect('env-updated', copy_images_files)
+    app.connect('config-inited', init_directive)
     return {'version': __version__}
diff --git a/sphinx_galleria/collector.py b/sphinx_galleria/collector.py
index e253e3c..01d551f 100644
--- a/sphinx_galleria/collector.py
+++ b/sphinx_galleria/collector.py
@@ -84,7 +84,7 @@ class GalleriaCollector(EnvironmentCollector):
 
                     images.append({
                         'title': imageglob['title'],
-                        'description': imageglob['description'],
+                        'alt': imageglob['alt'],
                         'thumb': os.path.relpath(
                             thumb_path_jpg,
                             app.env.srcdir),
diff --git a/sphinx_galleria/directive.py b/sphinx_galleria/directive.py
index 0ce7011..77f0158 100644
--- a/sphinx_galleria/directive.py
+++ b/sphinx_galleria/directive.py
@@ -17,6 +17,8 @@ from sphinx.writers.latex import LaTeXTranslator
 from sphinx.writers.texinfo import TexinfoTranslator
 from sphinx.writers.text import TextTranslator
 from sphinx.writers.manpage import ManualPageTranslator
+from sphinx.util.osutil import relative_uri
+from sphinx.locale import __
 
 
 class galleria(nodes.General, nodes.Element):
@@ -27,15 +29,30 @@ def html_visit_galleria(self: HTMLTranslator, node: galleria) -> None:
     galleria_id = 'galleria-%s' % uuid.uuid4()
 
     self.body.append(
-        "<div id='%s' class='%s'></div>" % (
+        "<div id='%s' class='%s' width='%s' height='%s'>" % (
             galleria_id,
-            node['class']
+            node['class'] + ' align-%s' % node['options']['align'],
+            node['options']['width'],
+            node['options']['height'],
         )
     )
 
+    if len(node['images']) > 0:
+        self.body.append("<figure><div class='row'>")
+        self.body.append("<img src='%s' title='%s' alt='%s'>" % (
+            node['images'][0]['image'],
+            node['images'][0]['title'],
+            node['images'][0]['alt']
+        ))
+        self.body.append('</div></figure>')
+
     self.body.append(
-        "<script>document.addEventListener('ready', function() {" +
-        "SphinxGalleria.run('%s', %s, dataSource=%s).init()});</script>" % (
+        "</div><script type='module'>" +
+        "import {SphinxGalleria} from './%s';\n" %
+        relative_uri(
+            self.builder.get_target_uri(self.builder.current_docname),
+            '_static/sphinxgalleria/sphinxgalleria.mjs') +
+        "new SphinxGalleria('%s', %s, %s).init();</script>" % (
             galleria_id,
             json.dumps(node['options']),
             json.dumps(node['images'])
@@ -47,66 +64,84 @@ def html_visit_galleria(self: HTMLTranslator, node: galleria) -> None:
 
 def latex_visit_galleria(self: LaTeXTranslator, node: galleria) -> None:
     for image in node['images']:
-        self.body.append('[%s]' % image['description'])
+        self.body.append('[%s]' % image['alt'])
     raise nodes.SkipNode
 
 
 def texinfo_visit_galleria(self: TexinfoTranslator, node: galleria) -> None:
     for image in node['images']:
-        self.body.append('[%s]' % image['description'])
+        self.body.append('[%s]' % image['alt'])
     raise nodes.SkipNode
 
 
 def text_visit_galleria(self: TextTranslator, node: galleria) -> None:
     for image in node['images']:
-        self.body.append('[%s]' % image['description'])
+        self.body.append('[%s]' % image['alt'])
     raise nodes.SkipNode
 
 
 def gemini_visit_galleria(self, node: galleria) -> None:
     for image in node['images']:
-        self.body.append('=> %s %s' % (image['path'], image['description']))
+        self.body.append('=> %s %s' % (image['path'], image['alt']))
     raise nodes.SkipNode
 
 
 def man_visit_galleria(self: ManualPageTranslator, node: galleria) -> None:
-    if 'description' in node.attributes:
-        self.body.append('[%s]' % node['description'])
+    if 'alt' in node.attributes:
+        self.body.append('[%s]' % node['alt'])
     raise nodes.SkipNode
 
 
+def align_choices(argument):
+    return directives.choice(argument, ('left', 'right', 'center'))
+
+
 class GalleriaDirective(Directive):
 
     has_content = False
     required_arguments = 1
     final_argument_whitespace = True
+
     option_spec = {
-        "class": directives.unchanged,
+        "class": directives.class_option,
         "galleria": directives.unchanged,
-        "description": directives.unchanged,
+        "alt": directives.unchanged,
         "title": directives.unchanged,
         "thumbsize": directives.unchanged,
         "transition": directives.unchanged,
+        'width': directives.length_or_percentage_or_unitless,
+        'height': directives.length_or_unitless,
+        'align': align_choices,
+        'hide_title': directives.flag,
+        'hide_alt': directives.flag,
     }
 
     def run(self):
-        if not self.state.document.hasattr('galleria_nodes'):
-            self.state.document.galleria_nodes = {}
+        source = self.state.document.settings._source
+        document = self.state.document
+        if not document.hasattr('galleria_nodes'):
+            document.galleria_nodes = {}
+        if source not in document.galleria_nodes:
+            document.galleria_nodes[source] = {}
 
-        galleria_name = self.options.get('galleria')
+        galleria_name = self.options.get('galleria') or uuid.uuid4()
         created = False
 
-        if galleria_name and \
-                galleria_name in self.state.document.galleria_nodes:
-            node = self.state.document.galleria_nodes[galleria_name]
+        if galleria_name in document.galleria_nodes[source]:
+            node = document.galleria_nodes[source][galleria_name]
 
         else:
             node = galleria()
             node['class'] = 'galleria'
             node['options'] = {
-                'transition': 'fade'
+                'transition': 'fade',
+                'label_prev': __('Previous'),
+                'label_next': __('Next'),
+                'label_close': __('Close'),
+                'label_thumbnail': __('Thumbnail, click to enlarge'),
             }
             node['images'] = []
+            document.galleria_nodes[source][galleria_name] = node
 
             created = True
 
@@ -115,12 +150,18 @@ class GalleriaDirective(Directive):
         if self.options.get('transition'):
             node['options']['transition'] = self.options['transition']
 
+        node['options']["width"] = self.options.get('width') or 'auto'
+        node['options']["height"] = self.options.get('height') or 'auto'
+        node['options']["align"] = self.options.get('align') or 'center'
+
         images_path = self.arguments
         for path in images_path:
             image = {}
-            image["description"] = self.options.get('description')
+            image["alt"] = self.options.get('alt')
             image["title"] = self.options.get('title')
             image["thumbsize"] = self.options.get('thumbsize') or '100x100'
+            image["hide_alt"] = bool(self.options.get('hide_alt'))
+            image["hide_title"] = bool(self.options.get('hide_title'))
             image["image"] = path
             node['images'].append(image)
 
diff --git a/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.css b/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.css
index e69de29..ce8d94c 100644
--- a/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.css
+++ b/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.css
@@ -0,0 +1,283 @@
+.sphinxgalleria-core {
+    text-align: center;
+}
+
+.sphinxgalleria-core.align-center {
+    margin: auto;
+}
+
+.sphinxgalleria-core.align-left {
+    float: left;
+}
+
+.sphinxgalleria-core.align-right {
+    float: right;
+}
+
+.sphinxgalleria-core figure .row {
+    flex-flow: row nowrap;
+    display: flex;
+}
+
+.sphinxgalleria-core figure .row button {
+    flex-grow: 1;
+    flex-shrink: 1;
+    cursor: pointer;
+}
+
+.sphinxgalleria-core figure .row button.button-modal {
+    flex-grow: 1000;
+    flex-shrink: 1000;
+    margin: 0;
+    padding: 0;
+    border: none;
+    width: max-content;
+    height: max-content;
+    display: flex;
+    flex-flow: column nowrap;
+}
+
+.sphinxgalleria-core figure .row button.button-modal .caption {
+    background-color: hsl(0, 0%, 34%);
+    color: white;
+    text-transform: none;
+    border-bottom-left-radius: .5rem;
+    border-bottom-right-radius: .5rem;
+    border: none;
+    margin: 0;
+    padding: .5rem 1.5rem .5rem 1.5rem;
+    width: 100%;
+    text-align: left;
+}
+
+.sphinxgalleria-core figure .row button.button-modal figcaption {
+    font-style: italic;
+    text-align: center;
+}
+
+.sphinxgalleria-core figure .row button.button-modal img {
+    margin: 0;
+    padding: 0;
+    border: none;
+    width: auto;
+    height: auto;
+    object-fit: contain;
+}
+
+.sphinxgalleria-core figure input[type=range] {
+    width: 100%;
+    height: 1.5rem;
+    border: none;
+    -webkit-appearance: none;
+}
+.sphinxgalleria-core figure input[type=range]:focus {
+    outline: none;
+    border: none;
+}
+.sphinxgalleria-core figure input[type=range]::-webkit-slider-runnable-track {
+    width: 100%;
+    height: .1rem;
+    padding: 0 1rem 0 1rem;
+    margin: 0;
+    border: none;
+    cursor: pointer;
+    animate: 0.2s;
+    background-color: hsl(0, 0%, 34%);
+}
+.sphinxgalleria-core figure input[type=range]::-webkit-slider-thumb {
+    height: 1rem;
+    width: 1rem;
+    border-radius: .5rem;
+    border: none;
+    background-color: hsl(0, 0%, 34%);
+    cursor: pointer;
+    -webkit-appearance: none;
+    margin-top: -.5rem;
+}
+.sphinxgalleria-core figure input[type=range]:focus::-webkit-slider-runnable-track {
+    background-color: hsl(0, 0%, 34%);
+    border: none;
+}
+.sphinxgalleria-core figure input[type=range]::-moz-range-track {
+    width: 100%;
+    padding: 0 1rem 0 1rem;
+    margin: 0;
+    border: none;
+    height: .1rem;
+    cursor: pointer;
+    animate: 0.2s;
+    background-color: hsl(0, 0%, 34%);
+}
+.sphinxgalleria-core figure input[type=range]::-moz-range-thumb {
+    height: 1rem;
+    width: 1rem;
+    border-radius: .5rem;
+    background-color: hsl(0, 0%, 34%);
+    cursor: pointer;
+}
+
+.sphinxgalleria-core .mask {
+    position: fixed;
+    top: 0;
+    left: 0;
+    height: 100vh;
+    width: 100vw;
+    margin: 0;
+    padding: 0;
+    background-color: hsla(0, 0%, 0%, 80%);
+    z-index: 1000;
+}
+
+.sphinxgalleria-core .submask {
+    height: 100%;
+    width: 100%;
+    margin: 0;
+    padding: 0;
+    position: relative;
+}
+
+.sphinxgalleria-core dialog {
+    position: absolute;
+    top: 3vh;
+    left: 0;
+    height: 90vh;
+    max-height: 90vh;
+    width: max-content;
+    margin: 0 auto 0 auto;
+    padding-left: 3rem;
+    padding-right: 3rem;
+    background-color: black;
+    color: white;
+    border: white solid 0.2rem;
+    border-radius: 0.5rem;
+    text-align: center;
+    display: flex;
+    flex-flow: column nowrap;
+}
+
+.sphinxgalleria-core dialog img {
+    height: 100%;
+    width: auto;
+    object-fit: contain;
+    flex-grow: 1000;
+    flex-shrink: 1000;
+    margin: 0.5rem 0 0.5rem 0;
+    padding: 0;
+}
+
+.sphinxgalleria-core dialog menu {
+    text-align: left;
+    width: 100%;
+    padding: 0;
+    margin: 0;
+}
+
+.sphinxgalleria-core dialog button {
+    border: none;
+    padding: .5em;
+    background-color: black;
+    color: white;
+}
+
+.sphinxgalleria-core dialog button:hover,
+.sphinxgalleria-core dialog button:focus {
+    background-color: hsl(0, 0%, 34%);
+    transition: background-color ease 0.4s;
+}
+
+.sphinxgalleria-core dialog header button {
+    position: absolute;
+    top: .5rem;
+    right: -.5rem;
+}
+
+.sphinxgalleria-core dialog header button::after {
+    content: '✕';
+}
+
+.sphinxgalleria-core dialog header {
+    position: relative;
+    min-height: 3rem;
+}
+
+.sphinxgalleria-core dialog menu {
+    height: 3rem;
+}
+
+.sphinxgalleria-core dialog header::after {
+    clear: both;
+}
+
+.sphinxgalleria-core dialog menu button.close {
+    float: right;
+}
+.sphinxgalleria-core dialog menu button.close::before {
+    margin-right: 0.5rem;
+    content: '✕';
+}
+
+.sphinxgalleria-core figure button.prev,
+.sphinxgalleria-core figure button.next {
+    background-color: hsl(0, 0%, 34%);
+    color: white;
+    height: 4rem;
+    width: 4rem;
+    margin: auto .5rem auto .5rem;
+    border-radius: 1rem;
+    border: none;
+}
+
+.sphinxgalleria-core figure button.prev:hover,
+.sphinxgalleria-core figure button.next:hover,
+.sphinxgalleria-core figure button.prev:focus,
+.sphinxgalleria-core figure button.next:focus {
+    background-color: hsl(0, 0%, 64%);
+    transition: background-color ease .4s;
+}
+
+.sphinxgalleria-core figure button.prev {
+}
+
+.sphinxgalleria-core figure button.next {
+}
+
+.sphinxgalleria-core figure button.prev::before,
+.sphinxgalleria-core dialog menu button.prev::before {
+    margin-right: 0.5rem;
+    content: '←';
+}
+
+.sphinxgalleria-core figure button.next::after,
+.sphinxgalleria-core dialog menu button.next::after {
+    margin-left: 0.5rem;
+    content: '→';
+}
+
+.sphinxgalleria-core ul.thumbnails {
+    overflow-x: hidden;
+    margin: 0 auto 0 auto;
+    padding: 0;
+    max-width: 100%;
+    height: max-content;
+    display: inline-flex;
+    flex-flow: row nowrap;
+    justify-content: flex-start;
+}
+
+.sphinxgalleria-core ul.thumbnails li {
+    list-style: none;
+}
+
+.sphinxgalleria-core ul.thumbnails li input[type=radio] {
+    display: none;
+}
+
+.sphinxgalleria-core ul.thumbnails li input:checked + label {
+    opacity: .5;
+}
+
+.sphinxgalleria-core ul.thumbnails li img {
+    margin: 0.5rem;
+    cursor: pointer;
+    max-width: unset;
+}
diff --git a/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.js b/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.js
deleted file mode 100644
index adc3f0e..0000000
--- a/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.js
+++ /dev/null
@@ -1,59 +0,0 @@
-"use strict";
-
-class SphinxGalleria {
-    constructor(target, options, data) {
-        var self = this;
-        self.target = target;
-        self.options = options;
-        self.data = data;
-
-        self.node_target = null;
-        self.node_figure = document.createElement('figure');
-        self.node_image = document.createElement('img');
-        self.node_caption = document.createElement('figcaption');
-        self.node_thumbnails = document.createElement('div');
-        self.node_dialog = document.createElement('dialog', modal=true);
-
-        var button_prev = document.createElement('button', id=self.target+"-prev")
-        var button_next = document.createElement('button', id=self.target+"-next")
-        button_prev.appendChild(document.createTextNode('<'));
-        button_next.appendChild(document.createTextNode('>'));
-
-        button_prev.onkeypress = self.onprev
-        button_prev.onclick = self.onprev
-
-        button_next.onkeypress = self.onnext
-        button_.onclick = self.onnext
-
-        self.node_figure.appendChild(self.node_image);
-        self.node_figure.appendChild(button_prev);
-        self.node_figure.appendChild(button_next);
-        self.node_figure.appendChild(self.node_caption);
-    }
-
-    init() {
-        var self = this;
-        self.node_target = document.getElementById(self.target);
-        self.node_target.innerHTML = '';
-        self.node_target.appendChild(self.node_figure);
-        self.node_target.appendChild(self.node_thumbnails);
-        self.node_target.appendChild(self.node_dialog);
-    }
-
-    onprev(event) {
-        var key = event.keyCode || event.charCode || event.which;
-        if(event.type==='keypress' && key!==13 && key!==32) {
-            return
-        }
-    }
-
-    onnext(event) {
-        var key = event.keyCode || event.charCode || event.which;
-        if(event.type==='keypress' && key!==13 && key!==32) {
-            return
-        }
-    }
-
-    changeImage() {
-    }
-}
diff --git a/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.mjs b/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.mjs
new file mode 100644
index 0000000..a80ebd7
--- /dev/null
+++ b/sphinx_galleria/static/sphinxgalleria/sphinxgalleria.mjs
@@ -0,0 +1,368 @@
+"use strict()";
+
+export class SphinxGalleria {
+    constructor(target, options, data) {
+        var self = this;
+        self.target = target;
+        self.options = options;
+        self.data = data;
+        self.oneimage = self.data.length === 1;
+
+        self.node_target = null;
+        self.node_figure = document.createElement('figure');
+        self.button_modal = document.createElement('button');
+        self.button_modal.setAttribute('aria-haspopup', 'dialog');
+        self.button_modal.setAttribute('class', 'button-modal');
+
+        self.node_image = document.createElement('img');
+        self.node_caption = document.createElement('figcaption');
+        self.node_alt = document.createElement('p');
+        self.node_alt.setAttribute('id', self.target+'-'+'alt');
+        self.node_image.setAttribute('aria-describedby', self.target+'-'+'alt');
+        self.node_thumbnails = document.createElement('ul');
+        self.node_thumbnails.setAttribute('class', 'thumbnails');
+        self.node_dialog = document.createElement('dialog');
+        self.node_mask = document.createElement('div');
+        self.node_mask.setAttribute('class', 'mask');
+        self.node_mask.hidden = true;
+        var node_submask = document.createElement('div');
+        node_submask.setAttribute('class', 'submask');
+
+        self.node_div_caption = document.createElement('div');
+        self.node_div_caption.setAttribute('class', 'caption');
+
+        var figure_row = document.createElement('div');
+        figure_row.setAttribute('class', 'row');
+
+        self.dialog_button_close = document.createElement('button');
+        self.dialog_button_close.setAttribute('class', 'close');
+
+        self.dialog_button_close_icon = document.createElement('button');
+        self.dialog_button_close_icon.setAttribute('aria-label', self.options.label_close);
+
+        self.dialog_image = document.createElement('img');
+        self.dialog_image.setAttribute('aria-describedby', self.target+'-'+'alt');
+
+        self.dialog_title = document.createElement('h1');
+        var dialog_header = document.createElement('header');
+        var dialog_menu = document.createElement('menu');
+
+        if(self.oneimage) {
+            self.node_thumbnails.hidden = true;
+            self.node_thumbnails.setAttribute('aria-hidden', true);
+            self.node_thumbnails.style.visibility = 'hidden';
+        } else {
+            self.node_slider = document.createElement('input');
+            self.node_slider.setAttribute('type', 'range');
+            self.node_slider.setAttribute('min', 1);
+            self.node_slider.setAttribute('max', self.data.length);
+            self.node_slider.setAttribute('value', 1);
+
+            self.button_prev = document.createElement('button');
+            self.button_prev.setAttribute('class', 'prev');
+            self.button_prev.setAttribute('aria-label', self.options.label_prev);
+
+            self.button_next = document.createElement('button');
+            self.button_next.setAttribute('class', 'next');
+            self.button_next.setAttribute('aria-label', self.options.label_next);
+
+            self.dialog_button_prev = document.createElement('button');
+            self.dialog_button_prev.setAttribute('class', 'prev');
+            self.dialog_button_next = document.createElement('button');
+            self.dialog_button_next.setAttribute('class', 'next');
+            self.dialog_button_prev.appendChild(document.createTextNode(self.options.label_prev));
+            self.dialog_button_next.appendChild(document.createTextNode(self.options.label_next));
+
+            figure_row.appendChild(self.button_prev);
+            dialog_menu.appendChild(self.dialog_button_prev);
+            dialog_menu.appendChild(self.dialog_button_next);
+        }
+
+        node_submask.appendChild(self.node_dialog);
+        self.node_mask.appendChild(node_submask);
+
+        figure_row.appendChild(self.button_modal);
+        self.node_figure.appendChild(figure_row);
+
+        self.node_div_caption.appendChild(self.node_caption);
+        self.node_div_caption.appendChild(self.node_alt);
+        self.button_modal.appendChild(self.node_image);
+        self.button_modal.appendChild(self.node_div_caption);
+
+        self.dialog_button_close.appendChild(document.createTextNode(self.options.label_close));
+
+        dialog_header.appendChild(self.dialog_title);
+        dialog_header.appendChild(self.dialog_button_close_icon);
+        self.node_dialog.appendChild(dialog_header);
+        self.node_dialog.appendChild(self.dialog_image);
+        dialog_menu.appendChild(self.dialog_button_close);
+        self.node_dialog.appendChild(dialog_menu);
+
+        if(!self.oneimage) {
+            figure_row.appendChild(self.button_next);
+            self.node_figure.appendChild(self.node_slider);
+        }
+    }
+
+    init() {
+        var self = this;
+        self.node_target = document.getElementById(self.target);
+        self.node_target.innerHTML = '';
+        self.node_target.setAttribute(
+            'class',
+            self.node_target.getAttribute('class') + " sphinxgalleria-core"
+        );
+        self.node_target.appendChild(self.node_figure);
+        self.node_target.appendChild(self.node_thumbnails);
+        self.node_target.appendChild(self.node_mask);
+
+        var onmodal = function(event) {
+            var key = event.keyCode || event.charCode || event.which;
+            if(event.type==='keypress' && key!==13 && key!==32) {
+                return;
+            }
+            event.preventDefault();
+            self.showModal();
+        };
+        self.button_modal.addEventListener('click', onmodal);
+        self.button_modal.addEventListener('keypress', onmodal);
+
+        var onclose = function(event) {
+            var key = event.keyCode || event.charCode || event.which;
+            if(event.type==='keypress' && key!==13 && key!==32) {
+                return;
+            }
+            event.preventDefault();
+            self.closeModal();
+        };
+
+        self.node_mask.addEventListener('click', onclose);
+        self.node_dialog.addEventListener('click', function(e) {e.stopPropagation();});
+        self.dialog_button_close.addEventListener('click', onclose);
+        self.dialog_button_close.addEventListener('keypress', onclose);
+        self.dialog_button_close_icon.addEventListener('click', onclose);
+        self.dialog_button_close_icon.addEventListener('keypress', onclose);
+
+        if(!self.oneimage) {
+            var onprev = function(event) {
+                var key = event.keyCode || event.charCode || event.which;
+                if(event.type==='keypress' && key!==13 && key!==32) {
+                    return;
+                }
+                event.preventDefault();
+                self.prev();
+            };
+
+            var onnext = function(event) {
+                var key = event.keyCode || event.charCode || event.which;
+                if(event.type==='keypress' && key!==13 && key!==32) {
+                    return;
+                }
+                event.preventDefault();
+                self.next();
+            };
+
+            self.button_prev.addEventListener('keypress', onprev);
+            self.button_prev.addEventListener('click', onprev);
+
+            self.button_next.addEventListener('keypress', onnext);
+            self.button_next.addEventListener('click', onnext);
+
+            self.dialog_button_prev.addEventListener('keypress', onprev);
+            self.dialog_button_prev.addEventListener('click', onprev);
+
+            self.dialog_button_next.addEventListener('keypress', onnext);
+            self.dialog_button_next.addEventListener('click', onnext);
+
+            self.dialog_image.addEventListener('click', function(e) {
+                var x = e.layerX - e.target.x;
+                if(x < e.target.width/2) {
+                    self.prev();
+                    e.preventDefault();
+                } else if(x > e.target.width/2) {
+                    self.next();
+                    e.preventDefault();
+                }
+            });
+
+            self.node_slider.addEventListener('change', function() {
+                var idx = self.node_slider.value - 1;
+                self.node_thumbnails.querySelector('input[data-index="'+idx+'"]').click();
+            });
+        }
+
+        self.data.forEach(function(image_data, idx) {
+            var image_element = document.createElement('li');
+            var image_button = document.createElement('input');
+            image_button.setAttribute('type', 'radio');
+            image_button.setAttribute('value', image_data.image);
+            image_button.setAttribute('name', self.target);
+            image_button.setAttribute('data-index', idx);
+            image_button.setAttribute('id', self.target+'-'+idx);
+            if(idx===0) {
+                image_button.checked = true;
+            }
+
+            image_element.appendChild(image_button);
+
+            var image_label = document.createElement('label');
+            image_label.setAttribute('for', self.target+'-'+idx);
+            image_element.appendChild(image_label);
+
+            var image_thumb = document.createElement('img');
+            image_thumb.setAttribute('src', image_data.thumb);
+
+            if(image_data.alt) {
+                image_button.setAttribute('data-alt', image_data.alt);
+                image_thumb.setAttribute('alt', image_data.alt);
+            } else {
+                image_thumb.setAttribute('alt', self.options.label_thumbnail);
+            }
+
+            if(image_data.title) {
+                image_button.setAttribute('data-title', image_data.title);
+            }
+            if(image_data.hide_alt) {
+                image_button.setAttribute('data-hide-alt', true);
+            }
+            if(image_data.hide_alt) {
+                image_button.setAttribute('data-hide-title', true);
+            }
+
+            if(image_data.transition) {
+                image_thumb.setAttribute('data-transition', image_data.transition);
+            }
+
+            image_label.appendChild(image_thumb);
+            self.node_thumbnails.appendChild(image_element);
+
+            image_button.addEventListener('change', function() {self.changeImage();});
+        });
+
+        self.node_target.addEventListener('keypress', function(event) {
+            var key = event.keyCode || event.charCode || event.which;
+
+            if(!self.oneimage && key===37) {
+                self.prev();
+            } else if(!self.oneimage && key===39) {
+                self.next();
+            } else if(key===27) {
+                self.closeModal();
+            }
+        });
+
+        self.changeImage();
+    }
+
+    prev() {
+        var self = this;
+        if(!self.oneimage) {
+            var idx = self.node_thumbnails.querySelector('input:checked').getAttribute('data-index');
+            idx = parseInt(idx) - 1;
+            if(idx < 0) {
+                idx = self.data.length - 1;
+            }
+            document.getElementById(self.target+'-'+idx).checked = true;
+            self.changeImage();
+        }
+    }
+
+    next() {
+        var self = this;
+        if(!self.oneimage) {
+            var idx = self.node_thumbnails.querySelector('input:checked').getAttribute('data-index');
+            idx = parseInt(idx) + 1;
+            if(idx > self.data.length - 1) {
+                idx = 0;
+            }
+            document.getElementById(self.target+'-'+idx).checked = true;
+            self.changeImage();
+        }
+    }
+
+    changeImage() {
+        var self = this;
+        var current = self.node_thumbnails.querySelector('input:checked');
+        var title = current.getAttribute('data-title');
+        var alt = current.getAttribute('data-alt');
+        var hide_title = current.hasAttribute('data-hide-title');
+        var hide_alt = current.hasAttribute('data-hide-alt');
+        var url = current.getAttribute('value');
+        var hide_caption = true;
+        var idx = parseInt(current.getAttribute('data-index'));
+
+        if(!self.oneimage) {
+            if(self.node_slider.value !== idx+1) {
+                self.node_slider.value = idx + 1;
+            }
+            var current_img = current.nextSibling.childNodes[0];
+            self.node_thumbnails.scrollTo({
+                left: current_img.x -
+                      self.node_thumbnails.offsetWidth/2 +
+                      current_img.clientWidth/2,
+                top: 0,
+                behavior: 'smooth'
+            });
+        }
+
+        if(!hide_title && title) {
+            self.node_caption.innerHTML = title;
+            self.node_caption.hidden = false;
+            self.dialog_title.innerHTML = title;
+            self.dialog_title.hidden = false;
+            hide_caption = false;
+        } else if(title) {
+            self.node_caption.innerHTML = '';
+            self.node_caption.hidden = true;
+            self.dialog_title.innerHTML = title;
+            self.dialog_title.hidden = false;
+        } else {
+            self.node_caption.innerHTML = '';
+            self.node_caption.hidden = true;
+            self.dialog_title.innerHTML = '';
+            self.dialog_title.hidden = true;
+        }
+
+        if(!hide_alt && alt) {
+            self.node_alt.innerHTML = alt;
+            self.node_alt.hidden = false;
+            hide_caption = false;
+        } else {
+            self.node_alt.innerHTML = '';
+            self.node_alt.hidden = true;
+        }
+
+        if(hide_caption) {
+            self.node_div_caption.hidden = true;
+        } else {
+            self.node_div_caption.hidden = false;
+        }
+
+        self.node_image.setAttribute('src', url);
+        self.dialog_image.setAttribute('src', url);
+    }
+
+    showModal() {
+        this.node_mask.hidden = false;
+        if(this.node_dialog.showModal) {
+            this.node_dialog.showModal();
+        } else {
+            this.node_dialog.open = true;
+            this.node_dialog.setAttribute('open', true);
+            this.node_dialog.setAttribute('aria-modal', true);
+            this.node_dialog.hidden = false;
+        }
+    }
+
+    closeModal() {
+        if(this.node_dialog.showModal) {
+            this.node_dialog.close();
+        } else {
+            this.node_dialog.open = false;
+            this.node_dialog.removeAttribute('open');
+            this.node_dialog.removeAttribute('aria-modal');
+            this.node_dialog.hidden = true;
+        }
+        this.node_mask.hidden = true;
+    }
+}