Need some Javascript relative path help with Responsive HTML 5 output please

I have my feedback working with the javascript code below linked to an image. Problem is that only the html files in the root are showing my image. How can I get the pages in subfolders to also find the image?

var mailSubject = 'Feedback on Offline Help File and/or Documentation';

var mailBody    = 'The page I was visiting was:  ' + location.href;

var mailDisplay = 'Email Feedback';

var bodyline =  '%0A%0APlease add your comments here:%0A%0A%0A%0A%0A%0A%0A%0AThank you for your valuable feedback.' ;

document.write(

  '<a title="Send Feedback on Help File and Documentation" href="mailto:xyz@company.com'

  + '?subject=' + escape(mailSubject)

  + '&body=' + escape(mailBody) + (bodyline)

  + '"><img src="./ImageRepository/feedbackicon.jpg" title="Email Feedback" border="none" alt="" /></a>'

);