Code blocks not rendered properly in smaller screens

I noticed an issue in which the code block in the "git log --oneline improvements" section renders badly in smaller screen. Further it also breaks the single-pagedness of the website. As a consequence, one might have to zoom in to read the post and scrolling might take you to empty space in the right. Screen shots:

• Desktop view:
  

• Mobile view (iPhone SE resolution)
  

  

  Note the scroll bar in the bottom of the page.

It would be nice to fix this by making the code blocks render in such a way that the code within the block is scrollable rather than the whole page being scrollable.

Note: Initially mentioned in https://github.com/git/git.github.io/pull/366#issuecomment-471316738

Inizia dalla sezione “git log --oneline improvements” sul sito Git Developer Pages collegato e riproduci il layout alla risoluzione di iPhone SE mostrata negli screenshot. Esamina gli stili responsivi che influiscono sui blocchi di codice; il lavoro è completato quando il codice stesso scorre orizzontalmente senza creare overflow sull’intera pagina o spazio vuoto.