When you create public Knowledge base(pkb) for your forec.com site, your site visitors will able to view the Knowledge Articles without any authentication as anonymous users and also vote for the articles. Here is an easiest way to do it for both desktop/mobile. 

AppExchange App : Public Knowledge for Mobile, Web and Facebook

Install URL : https://appexchange.salesforce.com/appxListingDetail?listingId=a0N300000059QxXEAU

Implementation Guide URL : https://appexchange.salesforce.com/servlet/servlet.FileDownload?file=00P3000000P3UNSEA3

This is a unmanaged package. The look and feel can be customise by editing the VF page code provided with the package.

Preview: