[FIX] website_event: adapt some layouts to new snippets and BS4

addons/website_event/data/event_demo.xml

@@ -9,15 +9,17 @@
             <field name="website_published">True</field>
             <field name="twitter_hashtag">odoo</field>
             <field name="description"><![CDATA[
-<section class="s_text_block_image_fw oe_img_bg" style="background-position: 50% 100%; background-image: url(/web/image/website.s_background_image_02);">
-   <div class="container">
-      <div class="row">
-         <div class="bg-black-25 col-lg-9 mb64 mt64">
-            <h2 style="font-size:62px">5 Intensive Days</h2>
-            <h4 class="text-muted"><font style="color: rgb(255, 255, 255); font-size: 24px;">to learn <i>Odoo Programming</i></font></h4>
-         </div>
-      </div>
-   </div>
+<section class="s_cover parallax oe_img_bg oe_custom_bg pt96 pb96" data-scroll-background-ratio="1">
+    <span class="s_parallax_bg" style="background-image: url('/web/image/website.s_background_image_02'); background-position: 50% 100%;"/>
+    <span class="s_parallax_filter"/>
+    <div class="container">
+        <div class="row s_nb_column_fixed">
+            <div class="col-lg-12 s_title bg-black-50" data-name="Title">
+                <h1 class="s_title_thin" style="font-size: 62px; text-align: center;">5 Intensive Days</h1>
+                <h4 class="text-muted" style="text-align: center;"><font style="color: rgb(255, 255, 255); font-size: 24px;">to learn <i>Odoo Programming</i></font></h4>
+            </div>
+        </div>
+    </div>
 </section>
 
 <div class="container">

addons/website_event/views/event_templates.xml

@@ -350,7 +350,7 @@
                 </div>
             </t>
 
-            <div class="card">
+            <div class="card mt-3">
                 <h4 class="card-header">When</h4>
                 <div class="card-body">
                     <i class="fa fa-clock-o"></i> From <span t-field="event.with_context(tz=event.date_tz).date_begin" t-options='{"hide_seconds":"True"}'> </span><br/>
@@ -358,7 +358,7 @@
                 </div>
             </div>
 
-            <div class="card" t-if="event.organizer_id">
+            <div class="card mt-3" t-if="event.organizer_id">
                 <h4 class="card-header">Organizer</h4>
                 <div class="card-body" t-field="event.organizer_id" t-options='{
                     "widget": "contact",
@@ -366,7 +366,7 @@
                     }'/>
             </div>
 
-            <div class="card">
+            <div class="card mt-3">
                 <h4 class="card-header">Social Stream</h4>
                 <div class="card-body">
                     <t t-call="website_mail.follow"><t t-set="object" t-value="event"/></t>