In what way is MJML responsive?

I came across MJML in a github repo for an org, and was like 'cool nice, email templates are hard and annoying, maybe this will finally make it easier'...

I'm not refutting that its probably nice to write and then make a quick template...but, in what way are these responsive???

If the web "responds" when the browser is tiny on phones or big on your wide screen PC monitor, all the example templates on the MJML site simply get smaller or bigger...they dont adjust the font size, thje layout, stylings in any other way... sooooo not really responding in the way I hoped / need.