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

Shouldn't the max-width of the #wrapper div be in % and not px?

How do you know when to use px and not % for a page as a general rule? Also, Nick says we're setting the #wrapper div to 940px. What is the actual width of this page?

2 Answers

Joel Bardsley
Joel Bardsley
31,249 Points

Hey Josh, hopefully this will help:

While you could set a % max-width to the wrapper ie 90%, it's better practice and more manageable to keep the wrapper at the div's native 100% width and then use padding or margin to keep content away from the edges (you'll notice in the video that Nick applied a 5% padding to the left and right to do that.

The max-width will depend on your chosen design. While you can absolutely have it set as a percentage, the percentage might look great for desktop but be completely unsuitable for smaller devices, or vice-versa. Instead of setting different widths at different screen sizes, a width is only being set once.

The next video in the series has Nick discussing a mobile-first approach so you'll be able to see that he's deliberately keeping everything as simple as possible from the start.

Hi Joe,

I guess my question is how did make the determination to set the max-width to 940px? Was that based off an assumption that there is a default page body width?