How to create Page variant Selection rule "if URL contains"? I want my variant to apply to all pages if the URL contains a certain string, eg: "cars".

So the cars variant should apply to cars, cars/toyota, cars/toyota/camry, etc.

Is there a way to use a wild card (cars/*?)?

I can't find any documentation on this. 

Thanks
Try under Variant -> Selection rules, in the pulldown Select:URL Path then Add. In the new dialog box, select "Allow access to the following pages" then enter "cars/*" in the textarea, then save. According the description below the textarea which says 

The '*' character is a wildcard. Example paths are blog for the blog page and blog/* for every personal blog.