Transit Visa for Sri Lankan who has a PR Card in Canada

Hello:

I am a Canadian permanent resident (PR) and holding Sri Lankan passport. I have an air ticket connecting in Hong Kong and Beijing. I am not going to come out of the terminal however I may have to spent couple of hours to get in to connecting flight. Do I need a “Transit type” if yes, how and where to apply. Please note I am living in Alberta, Canada.

Thank you

S