Merge branch '25-videos-have-different-size' into 'master'

Resolve "Videos have different size/layout depending on source"

Closes #25

See merge request decker/decker!63

src-support/decker.scss

@@ -497,7 +497,7 @@ body {
 
         video {
           width: 100%;
-          margin: 0 auto;
+          margin: 0;
           display: block;
         }