Full screen canvas but scaled game area

I’m trying to duplicate the functionality of this createjs game:

https://showcase.codethislab.com/games/whack_em_all/

is there an easy way to do it with the scale class or do I kind of need to take take of the scaling manually with javascript?

I’m also going to post this in the phaser 3 group in case there’s a better way with version 3.