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CSS Unused CSS Stages Flexbox and Multi-Column Layout Flexbox: Part 1

Posted by nicolasdeknoop
nicolasdeknoop
6,943 Points

Hello there, just a quick question, why the universal selector * {box-sizing: border-box}? Thanks in advance!

i thought that basically universal selectors should be avoided due to their over-reaching power. (Perhaps in context, some developers not in favour of a hard-reset - margin:0; padding: 0;). Is this necessary for working with flexbox?

4 Answers

Josh Alling
Josh Alling
17,172 Points
Josh Alling
Josh Alling
17,172 Points

You don't have to avoid using the universal selector completely, but it should only be used when you want every single element on the page to have the same attribute. In this case, you are giving every element the border-box attribute to make sure that all borders fit within the width and height of their elements.

Hope this helps.

nicolasdeknoop
nicolasdeknoop
6,943 Points

Thanks Josh

Gabriel Roczanski
PLUS
Gabriel Roczanski
Courses Plus Student 2,136 Points
Gabriel Roczanski
Gabriel Roczanski
Courses Plus Student 2,136 Points

P.S, sorry my bad english.

Box-sizing will assists in edge and margin accounts, in which case it is applied makes all the tags. It won't reset, just set that all your tags will have the box-sizing: border-box.

nicolasdeknoop
nicolasdeknoop
6,943 Points

Thanks Gabriel

nicolasdeknoop
nicolasdeknoop
6,943 Points
nicolasdeknoop
nicolasdeknoop
6,943 Points

Thought this may be of interest regarding universal selector usage over and above box-sizing (and hard-reset) ----- transitions, non-repeating backgrounds, relative positioning, and middle-alignment:
http://css-tricks.com/things-it-might-be-funuseful-to-try-the-universal-selector-on/

Kevin Korte
Kevin Korte
28,149 Points
Kevin Korte
Kevin Korte
28,149 Points

I immediately thought of this article reading this: http://www.paulirish.com/2012/box-sizing-border-box-ftw/

If you haven't you should, it's short.

nicolasdeknoop
nicolasdeknoop
6,943 Points

Thanks Kevin, I'll check it out!