RH2015 Issue with Positioned Text Box Remaining in Place Over Image

Using RH2015 I have located a Positioned Text Box over an image and configured a Trigger from text in content up page from the image to Show/ Hide the (effect) Positioned Text Box on click. The issue I see is the text box does not remain positioned relative to the image on which it is overlaid. Is the positioning of a Positioned Text Box relative to the Trigger in this case, rather than relative to the image as desired? I am using a Responsive HTML5 output so would like to have a solution that would flow relative to the image position and scale changes, remaining anchored.