Why define the ul {margin: 0; padding: 0;} selector in the css file?

Why define the ul {margin: 0; padding: 0;} selector in the css file?

Why define the ul {margin: 0; padding: 0;} selector in the css file?

Ul labels have padding values by default in FF, while only margin has default values in IE. What are the default values of padding and margin in the following views?

IE effect:

 

IE result: margin-left: The default value is 40px;

 

FF effect:

 

 

Firefox result: padding-left: 40px;

 

Wekkit effect:

Webkit padding-left: 40px;

 

Webkit results are the same as Firefox: padding-left: 40px;

Based on the default values of ul's margin and padding, ul {margin: 0; padding: 0;} is set to unify the attributes of ul's margin and padding in most browsers. .

HTML:

CSS:

Body, ul {padding: 0; margin: 0 ;}# box {width: 600px; height: 100px; background: blue; cursor: hand ;}li {width: 600px; height: 20px; background-color: red ;}