Remove the gap between audio, canvas, iframes, images, videos and the bottom of their containers

see h5bp/html5-boilerplate#1613

Author: mrmartineau

assets/src/scss/components/_embedded-content.scss

@@ -23,3 +23,17 @@ svg:not(:root) { overflow: hidden; }
 img, object, embed, video {
 	max-width: 100%;
 }
+
+/**
+ * Remove the gap between audio, canvas, iframes,
+ * images, videos and the bottom of their containers:
+ * https://github.com/h5bp/html5-boilerplate/issues/440
+ */
+audio,
+canvas,
+iframe,
+img,
+svg,
+video {
+	vertical-align: middle;
+}