Window manager shortcuts should have the ability to resize windows

There is a website I go to that when I click a link in it it always opens a webpage that basically is the size of my entire screen. Every time, I need to resize it so I can see other things on my screen. I would like Window Manager's shortcuts to have the ability to resize windows and not just move them to different places. I know I can go to the app in the Menubar and select a different size, but a keyboard shortcut would be much more convenient.