Common selectors are

Common selectors are ：

        1、 tag chooser ;2、 Class selectors ;3、ID Selectors ;4、 Global selector ;5、 Combination selector ;6、 Inheritance selector ;7、 Pseudo class selector .

The first is tag chooser , It also becomes an element selector . The basic form of tag selector is as follows ：tagName{property:value}, among tagName It's the label name ,property yes css Properties of .

The second is Class selectors , Class selectors are used to define the same rendering for a series of tags , The common grammar is .classValue{property:value}. among classValue Is the name of the class selector , This is from css The author names himself .

The third is ID Selectors ,ID A selector defines a particular html Elements , Only one tag or element in a web page uses a ID The attribute value .ID The basic syntax format of the selector is as follows ：

#idValue{property:value}. among idValue yes ID The name of the selector , Can be CSS The writer writes it himself .

The fourth is Global selector , The global selector is for all htmlz Elements work . The grammar format is ： *{propery:value}. among “*” Indicates that it works on all elements ,property Express css Properties of ,value Represents the property value .

The fifth is Combination selector , Is to match multiple selectors , It can form a compound selector , Also known as composite selector .

The sixth is Inheritance selector , The rule of inheritance is that child tags are undefined , The selector inheriting the parent tag ; When the child tag repeatedly defines the declaration of the parent tag , Execute the sub tag selector .

Seventh hour Pseudo class selector , Pseudo class selectors are mainly used in <a> On the label , It consists of four states ： No access to the link （link）、 Visited link （visited）、 Activate Links （active）、 Mouse over the connection (hover).