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CSS How to Make a Website CSS: Cascading Style Sheets Center the Wrapper

Posted by Jim Withington
Jim Withington
12,025 Points

Where did the 400 pixels part come from? What makes this "centering" rather than simply "specifying width?"

I got lost here a bit because the video says "look how this is centered," but that's not how it seems. He also mentioned that under 400 pixels will do something different, but doesn't explain why—how does that work?