Drupal 8 override administration theme node form css I need to override some of the styles on the Seven node form. My initial thought is to alter the form and add a custom css file. Is there a better Drupal 8 way to achieve this?

Thanks,

Dave
If you only has to add some custom css form alteration will does it. 

If you also have to make some changes in field templates, or some theme function alteration, I suggest you to create your custom theme, and add Seven as a base theme