You don't know JS is also a great place to start.
+1 from me for Codecademy!
I second anything from Treehouse.
The Treehouse Course is excellent
I would recommend Udacity course
I'd echo a bunch of the comments here. I also suggest diving in and trying to code an interface such as GMail. I've always found that I learned more by coding and running into roadblocks vs going through a course.
When you say "specifically for UI/UX designers"? Do you mean a course with UI-oriented examples?
Because it's trendy
How much do you know already? What are you hoping to target with the "crafted specifically for UI.UX Designers" distinction?
Learn Code Academy on Youtube is fantastic.
If you are a visual learner like me, my money is on a pluralsight subscription for as long as you need to watch the courses you need. They have the most professional and technically in-depth courses you could want that go from beginner to pro.
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