📜  CSS :where() 伪类

📅  最后修改于: 2022-05-13 01:56:30.459000             🧑  作者: Mango

CSS :where() 伪类

:where() 伪类有助于在较长的 CSS 选择器列表中最小化较长的代码。它避免了重复,只需用一个选择器替换多个选择器。在 :where() 伪类中,您也可以覆盖。

句法:

class_Name :where(html-tages) html-tag {
    /* CSS code */
}

没有 :where() 伪类的选择器:

.className li em,
.className section em,
.className p em {
    // CSS code
}

带有 :where() 伪类的选择器:

className :where(li, section, p) em {
    //CSS code
}

示例 1:

HTML


  

    

  

    

        GeeksforGeeks     

       

CSS The :where() pseudo-class

       
    
        

            A computer science portal              for geeks.         

        
                   
                             Geeks classes an extensive                  classroom programme.                      
    
  


HTML


  

    

  

    

        GeeksforGeeks     

    

        CSS :where() pseudo-class     

    
    
        

This is GeeeksforGeeks website


        

                             If it will not override, then                  the background colour of this                  text is purple                      


        
                             If it will override, then the                  background colour of this text                  is green                      
    
  


输出:

伪类在哪里

示例 2:很容易覆盖 :where() 伪类,如下例所示。

HTML



  

    

  

    

        GeeksforGeeks     

    

        CSS :where() pseudo-class     

    
    
        

This is GeeeksforGeeks website


        

                             If it will not override, then                  the background colour of this                  text is purple                      


        
                             If it will override, then the                  background colour of this text                  is green                      
    
  

输出:

伪类在哪里

浏览器支持:

  • 火狐 78+
  • Chrome 72(通过实验性网络平台功能启用它)