Would Putting All My External Css On One Line Be Bad For Seo?
I want to do this to make my css look all jumbled up and thereby discourage anyone looking to steal it. So will this be bad for seo or do search engine robots not scan the external css file at all?
Spiders/bots can read your style sheets no matter how you format them.
With regards to SEO and ranking, there is no evidence that style sheets have any effect, positive or negative except if you put white text on a white background (or black on black etc). The only reason someone would do that is for spamming keywords into your page.
So, go ahead and jumble it up! But you should keep a nicely formatted version in case you want to make changes.