I'm writing a plugin, which has a certain style. However, that style won't suit every site. therefore, I would like to let the site admin override the plugin CSS if they want.
How would I go about doing that?

I'm also trying to think of a way to let a theme override the plugin CSS.   
I could go the way [this answer][1] or [this answer][2] suggest:

 - Provide a way to disable the plugin CSS; 
 - Enqueue the plugin CSS using a hook, by which letting the theme unhook it; 
 - Trust the theme devloper to know they can enqueue the theme's own styles with the plugin styles as a dependency.  

But I'm not sure if the ways suggested are just ways to solve the problem after the plugin is already written, or are best practice.  
On the other hand, I was thinking maybe in my plugin I could check for a specific CSS file in the theme, and - if it exists - enqueue it after the plugin CSS. Does that make sense?


  [1]: http://wordpress.stackexchange.com/questions/2680/best-way-to-overide-plugin-css#answer-2681
  [2]: http://wordpress.stackexchange.com/a/101038/373