What is CSS?
CSS is short for cascading style sheets.
CSS is a markup language, which belongs to browser interpreted language. It can be executed directly by the browser without compilation.
CSS is a markup language used to represent HTML or XML.
CSS is recommended and maintained by the CSS working group of W3C
CSS is a required course for beginners of programming. Using CSS style can make the page beautiful.
CSS syntax consists of three parts: selectors, properties, and values
CSS3 is the latest CSS standard.
CSS3 has more style settings than CSS. CSS3 is forward compatible, that is, valid codes in CSS are also valid in CSS3.
A code that is valid for both CSS and CSS3. If the browser does not support CSS3, it will only be displayed in the style of CSS. The most common is the arc angle.
A code that is only valid in CSS3. If the browser does not support CSS3, its display effect will not appear. CSS3 and CSS are exactly the same when writing code, except for setting some new attributes in CSS3.
CSS3 new properties
Box shadow (shadow effect)
Border colors (set multiple colors for the border)
Text overflow (text truncation)
Box sizing (composition mode of control box model): specify that two boxes border
Resize: specifies a div element that allows the user to resize
Outline (outer border)
Background origin (specify where the background picture starts to be displayed)
Background clip (specify where the background picture is cut)
Background (specify multiple backgrounds for an element)