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HTML Introduction to HTML and CSS (2016) Adding a New Web Page Write the CSS

Aakash Srivastav
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.a{fill-rule:evenodd;}techdegree
Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 Points

margin and padding

I have always seen writing this code in the beggining of the css document. Is it necessary to write? What does it actually do?

*,html{
    margin: 0;
    padding: 0;
}

2 Answers

This selector generally targets the entire document and sets all of the margins and padding to 0 before you've got started, essentially giving you a level playing field to work from. In earlier videos you have maybe seen the teachers using something called normalize.css. This is essentially the same concept except it is only resetting margins and padding as oppose to a whole array of properties.

*, html {
     margin: 0;
     padding: 0;
}

The star or asterisk (*) generally means you're selecting "all". Basically what you are doing is selecting all the elements on the document and setting the margin to 0, and padding to 0.

The CSS used above will strip off the margins and padding from the <html> element, if any apply. (Some browsers will automatically add margins or padding to the <html> element, so this CSS will override the default browser styling)

Since each browser is different, there are different default setting for each browser.