diff --git a/prosopopee/themes/light/templates/sections/bordered-picture.html b/prosopopee/themes/light/templates/sections/bordered-picture.html
index 3d23ffa..53474ed 100644
--- a/prosopopee/themes/light/templates/sections/bordered-picture.html
+++ b/prosopopee/themes/light/templates/sections/bordered-picture.html
@@ -5,16 +5,17 @@
 {% endif %}
 {% if section.image.type == "video" %}
 {% set video = Video(section.image) %}
+{% set format = settings.ffmpeg.extension %}
 {{ video.copy() }}
 {% else %}
 {% set image = Image(section.image) %}
-{% set caption = section.text %}
 {{ image.copy() }}
 {% endif %}
+{% set caption = section.text %}
 {% if video %}
 <section class="bordered-picture">
-  <video class="lazy" id="video" poster="{{ pathstatic }}/{{ video.generate_thumbnail("800") }}" alt="" autoplay="autoplay" loop="loop" preload="auto" muted>
-    <source src="{{ pathstatic }}/{{ video }}" type="video/webm" data-source="{{ video }}" data-format="vp8" data-extension="webm">
+  <video class="responsive-video" id="video" poster="{{ pathstatic }}/{{ video.generate_thumbnail("800") }}" alt="" autoplay="autoplay" loop="loop" preload="auto" muted>
+    <source src="{{ pathstatic }}/{{ video }}.{{ format }}" type="video/{{ format}}">
     </video>
 </section>
 {% else %}
diff --git a/prosopopee/themes/light/templates/sections/full-picture.html b/prosopopee/themes/light/templates/sections/full-picture.html
index 309e067..c709961 100644
--- a/prosopopee/themes/light/templates/sections/full-picture.html
+++ b/prosopopee/themes/light/templates/sections/full-picture.html
@@ -5,6 +5,7 @@
 {% endif %}
 {% if section.image.type == "video" %}
 {% set video = Video(section.image) %}
+{% set format = settings.ffmpeg.extension %}
 {{ video.copy() }}
 {% else %}
 {% set image = Image(section.image) %}
@@ -13,8 +14,8 @@
 <div class="full-picture">
     <div class="image">
         {% if video %}
-        <video autoplay loop muted class="fillWidth">
-          <source src="{{ pathstatic }}/{{ video }}" type="video/webm" data-source="{{ pathstatic }}/{{ video }}" data-format="vp8" data-extension="webm">
+        <video autoplay loop muted class="fillWidth responsive-video">
+          <source src="{{ pathstatic }}/{{ video }}.{{ format }}" type="video/{{ format}}">
         </video>
         {% else %}
         <img  src="{{ pathstatic }}/{{ image.generate_thumbnail("x800") }}">
diff --git a/prosopopee/themes/light/templates/sections/pictures-group.html b/prosopopee/themes/light/templates/sections/pictures-group.html
index e557afc..8e61cee 100644
--- a/prosopopee/themes/light/templates/sections/pictures-group.html
+++ b/prosopopee/themes/light/templates/sections/pictures-group.html
@@ -7,18 +7,18 @@
     {% for line in section.images %}
     {% for image in line %}
     {% if image.type == "video" %}
-    {% set caption = image.text %}
     {% set video = Video(image) %}
+    {% set format = settings.ffmpeg.extension %}
     {{ video.copy() }}
     {% else %}
-    {% set caption = image.text %}
     {% set image = Image(image) %}
     {{ image.copy() }}
     {% endif %}
+    {% set caption = image.text %}
     <div class="image">
         {% if video %}
-        <video id="video" poster="{{ pathstatic }}/{{ video.generate_thumbnail("800") }}" alt="" autoplay="autoplay" loop="loop" preload="auto" muted>
-          <source src="{{ pathstatic }}/{{ video }}" type="video/webm" data-source="{{ pathstatic }}/{{ video }}" data-format="vp8" data-extension="webm">
+        <video class="responsive-video" id="video" poster="{{ pathstatic }}/{{ video.generate_thumbnail("800") }}" alt="" autoplay="autoplay" loop="loop" preload="auto" muted>
+          <source src="{{ pathstatic }}/{{ video }}.{{ format }}" type="video/{{ format }}">
         </video>
         {% set video = "" %}
         {% else %}