small fixes

src/download.audio.html

@@ -44,7 +44,7 @@ include "includes/head.html"
     include "includes/js.html"
 
     <!-- build:js /scripts/vendor/video.js -->
-    <script src="bower_components/videojs/dist/alt/video.novtt.min.js"></script>
+    <script src="bower_components/videojs/dist/video.min.js"></script>
     <!-- endbuild -->
 
 </body>

src/download.video.html

@@ -43,7 +43,7 @@ include "includes/head.html"
     include "includes/js.html"
 
     <!-- build:js /scripts/vendor/video.js -->
-    <script src="bower_components/videojs/dist/alt/video.novtt.min.js"></script>
+    <script src="bower_components/videojs/dist/video.min.js"></script>
     <!-- endbuild -->
 
 </body>

src/styles/main.css

@@ -6562,6 +6562,11 @@ html {
 #md-preview {
   padding-bottom: 30px;
 }
+
+video, audio {
+  margin: 0 auto;
+  width: 100%;
+}
 .wrap {
   width: 40%;
   height: 40%;