CSS stands for cascading style sheet, and they describe how elements should be displayed on a screen. CSS can describe many different webpages at once. Without CSS, web developers would have more work, more length, and more money put into their designing.
The syntax of CSS consists of a selector and a declaration block. A selector is the indictor of the HTML you want to style. A declaration block contains one or more CSS properties describing HTML. Declaration blocks are separated by semicolons. Each CSS property is a name and a value that is separated by a colon. The whole CSS declaration block is surrounded by a curly bracket.
CSS selectors are used to find the HTML elements you want to style. There are five different categories of CSS selectors: simple selectors, combinator selectors, pseudo-class selectors, pseudo-elements selectors, and attribute selectors. The different types of selectors are used for different parts of the elements.