幸福清风

html-css练习题（系统提示）

 
    代码赏析： 
   
    DOCTYPE html 
    > 
   
     lang= 
    "en" 
    > 
   
     charset= 
    "UTF-8" 
    > 
   
     name= 
    "viewport" 
     content= 
    "width=device-width, initial-scale=1.0" 
    > 
   
     http-equiv= 
    "X-UA-Compatible" 
     content= 
    "ie=edge" 
    > 
   
    </span>Document 
    <span style="color:#800000;">