am 51372cd2: docs: update "na" style to make opaque, add dropshadow, and re-order z-index to be on top of images

* commit '51372cd2e564f411ad80821c7adad210bea7d8b7':
  docs: update "na" style to make opaque, add dropshadow, and re-order z-index to be on top of images