Jupyter Notebook 7 look

Hi, installed Jupyter Notebook 7 on my system and I must say I prefer the 6.5.5 look. Is it possible to revert to the 6.5.5 look? I saw there is a way to launch the Notebook Classic in the old theme but I like to use the new features with the old look.

Aside from the font, size (which is easy to adjust) I prefer the more detailed borders of 6.5.5 and the borders on the icons in the toolbar. Also my usual trick to extend the window to the full size of the browser doesn’t work on v7:

from IPython.display import display, HTML
display (HTML("<style>.container { width:100% !important; }</style>"))

I can’t understand how there is no built-in feature for that. Not everyone likes coding like it’s a blog page…