HTML 和 CSS 基础

    
    
    
    



    
Hello World
    
2 header
    
3级标题
    
4jibiaoqian 
    
5jibiaoqian 
    
6jibiaoqian 
    
this is a paragraph
    
here you are with class name p2 using ".p2"
    
here is related id number p3 using "#p3"
    

        
div中嵌套的p
    
    change to baidu
    

结果：

HTML的DOM和CSS渲染的基础。