Added youtube iframe template

Author: AngelOnFira

sass/_extra.scss

@@ -88,3 +88,18 @@ h6:hover .anchor {
         margin-bottom: 32px;
     }
 }
+
+.ratio169 {
+    position: relative;
+    width: 100%;
+    height: 0;
+    padding-bottom: 56.25%;
+
+    & > iframe {
+        position: absolute;
+        left: 0;
+        top: 0;
+        width: 100%;
+        height: 100%;
+    }
+}

templates/shortcodes/youtube.html

@@ -0,0 +1,6 @@
+<figure class="inline-image">
+	<div class="ratio169">
+		<iframe width="100%" src="https://www.youtube.com/embed/{{ id }}" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
+	</div>
+	{% if caption %}<figcaption><p>{{caption}}</p></figcaption>{% endif %}
+</figure>