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HTML HTML Tables Table Basics Overview of Tables

Alex Rodriguez
Alex Rodriguez
Front End Web Development Techdegree Student 20,810 Points

What is this code doing in the begging on the main.css?

I open up the project files on the top of the main.css this code shows up

*, *:before, *:after { -moz-box-sizing: border-box; -webkit-box-sizing: border-box; box-sizing: border-box; }

What is this doing? I m having a hard time understanding.

Thank you

3 Answers

Ryan Field
Ryan Field
Courses Plus Student 21,242 Points

Hi, Alex. That bit of code is making it so that elements on the site will include the border and padding inside the total size of elements. Normally, if you have a 200px by 200px div, for example, any padding and borders will be calculated in addition to that, meaning your final element will be larger than 200px by 200px. With box-sizing: border-box;, however, this ensures that any padding and borders will be included inside the total, so your elements are always the size you specify them to be. The asterisk (*) is a universal selector, and will select all elements anywhere on the page.

."*"... means all elements, ":before" and ":after " are pseudo-elements

That code only sets the default box sizing for elements and pseudo-elements on the page