This from their website:
"Our Shopper Website works best with the Google Chrome Internet Browser version 35 or newer. If you are using a different browser, you may encounter problems with the website's functionality. Our website is also supported on Internet Explorer version 9 or newer, Firefox version 24 or newer, and Safari version 6.20 or newer. If your browser is out of date, please update and try again. Please also verify that you have JavaScript enabled as this is needed for the site to function properly. If you still encounter any problems using the website, please let us know what operating system and internet browser you are using to access the Shopper Website to help us better troubleshoot your issue."