Will google ignore words that are inside the elements that are set to \"display: none\" in css?
Example:
If you hide your menu with javascript the search engines will likely not be able to follow the links. I have used dislay:none to hide chunks of navigation which I don't want to appear on certain areas of a website. There are a some CMS sytsems build to show navigation this way and if Google banned all sites built with those CMS systems then it might not be providing the most relevant results.
If you are using it to hide text just for seo purposes stay away from that. It is likely the search engines will not pick it up but if they do - for example if a competitor flags it to Google - and you are using it to hid spammy text then be prepared for the consequences.