I-frames can be added to any page with a "Type / Template" of "generalas follows:  (these include videos, vendor product embeds, etc)

  1. Create the page
  2. Edit Page Options and set the page width to "full-width" ( Options is on the top right of the page.)
  3. Select the "Content" Dock from the Dropdown list of available Docks on this page.
  4. Add a Rich Content widget from the Widget Library.  (Click and drag the widget from the library to the just below the dock name )  See How! See how!
  5. Edit the widget content and click on the "Source" button in the top menu bar of the editor frame.  This puts you into HTML mode, where you can enter HTML tags and styling
  6. add the iframe script using the following generic format: <div class="embed-responsive embed-responsive-16by9"><iframe src="http://iframes.ovnight.com/engagement-rings/halo/round" style="display: block; margin: auto; height: full; width: 100%; border: none;"></iframe></div> 
  7. Replace the RED text above with your own code.
  8. Save the page and take a look at it on the front end to see how you did.