docs: use meta tag to set demo height

docs/index.md

@@ -9,8 +9,6 @@ position: 1
 
 The following application demonstrates how the Kendo UI components for Angular look like when styled with the Kendo UI Default theme for Angular.
 
-<style>
-.demo-embed .runner { height: 2200px; }
-</style>
-
+{% meta height:2200 %}
 {% embed_demo ../preview-app/ %}
+{% endmeta %}