W3.CSS 边框

边框通常用于在框或表格单元格或任何其他 HTML 元素周围显示轮廓。在 W3.CSS 中，有不同的类可用于添加或删除边框。用于添加边框的类称为加法类，用于移除边框的类称为减法类。

添加剂边界类：

Sr. No.	Class Name	Description
1.	w3-border	It is used to add a border around the targeted element.
2.	w3-border-top	It is used to add a top border to the targeted element.
3.	w3-border-bottom	It is used to add a bottom border to the targeted element.
4.	w3-border-right	It is used to add a right border to the targeted element.
5.	w3-border-left	It is used to add a left border to the targeted element.

减法边界类：

Sr. No.	Class Name	Description
1.	w3-border-0	Removes all the border from the targeted element.

例子：

HTML

  

    
    
            
     

  

    
    
    

        
        
        
GeeksForGeeks
    
      
    
    

        
Additive Border Classes
 
             
             
             
             
            
    
      
    
    

        
Subtractive Border Classes
 
         
        
    

输出：

边框颜色：可以使用以下 W3.CSS 中可用的边框颜色类将任何颜色添加到边框。如果您想要任何其他自定义颜色，则可以使用 CSS 属性手动设置它。

例子：

HTML

  

  
    
    
     

  

    
    
    

        
        
        
GeeksForGeeks
    
      
    
    

        
Coloured Border
 
         
        
        
        
        
    
      
    
    

        
Hoverable Coloured Border
 
         
        
        
        
        
    

输出：

粗边框：

您可以使用 W3.CSS 边框类向目标元素的任何一侧添加粗边框。

Sr. No.	Class Name	Description
1.	w3-bottombar	It is used to add a thick border at the bottom of the targeted element.
2.	w3-leftbar	It is used to add a thick border at the left side of the targeted element.
3.	w3-rightbar	It is used to add a thick border at the right side of the targeted element.
4.	w3-topbar	It is used to add a thick border at the top of the targeted element.

例子：

HTML

  

  
    
    
            
     

  

    
    
    

        
        
        
GeeksForGeeks
    
      
    
    

        
Thick Border Classes
 
         
        
        
        
    

  

输出：