https://www.w3schools.com/css/css_syntax.asp
A CSS rule consists of a selector and a declaration block.
CSS Syntax
The selector points to the HTML element you want to style.
The declaration block contains one or more declarations separated by semicolons.
Each declaration includes a CSS property name and a value, separated by a colon.
Multiple CSS declarations are separated with semicolons, and declaration blocks are surrounded by curly braces.
Example
In this example all <p> elements will be center-aligned, with a red text color:
p {color: red;
text-align: center;
}
Example Explained
pis a selector in CSS (it points to the HTML element you want to style: <p>).coloris a property, andredis the property valuetext-alignis a property, andcenteris the property value
You will learn much more about CSS selectors and CSS properties in the next chapters!
标签：css02,color,text,value,Syntax,declaration,property,CSS From： https://www.cnblogs.com/emanlee/p/18218795