Inbox by Gmail - making a small application

Now, I know some of us hate Google, but they have come up with a really good service at Inbox. I find it very easy to manage email that way and have been using it on my Windows PC as a chrome application for years now.

Recently, I bought a MacBook Pro and just plain hate the default mail application they have installed. Also, since I own an Android phone and I use the Inbox Android Application there, it's really hard to see what I did in inbox reflected on Mail (see footnote)

My problem is that when I install the Inbox chrome extension, it is little more that a glorified shortcut. On my Windows PC, I used to select 'Open as a separate Window' and I didn't need to use Chrome at all. However, on the Mac there is no such option and it opens Chrome every time I open Inbox (on top of that I cannot pin the application to the Dock like I used to be able to with the Taskbar). So the question is whether I can make a small application that I can pin to the Dock, which opens a fullscreen window showing the contents of the Inbox website.

I am a Mac newbie so please forgive me for any noobie things I said. Any help would be greatly appreciated!

(footnote) For example, you can mark an email as 'Done' in Inbox. Now I don't know where that email disappears on my Mac.