Check out example codes for "adding css to html body". It will help you in understanding the concepts better.

Code Example 1

Three ways to add CSS to the body of html:
	1)External CSS
	2)Internal CSS
	3)Inline CSS

1) Externally:  
    Type your css code in a file. Remember you file name.
	<link rel="stylesheet" type="text/css" href="FileName.css" >

2) Internally:
	Type your cSS in the html file itself. (It is not preffered until
	little CSS code is to be added). This can be done by style tag.
	h1 {
      text-size: 0.8em;

3) Inline:
	This method is not used by developers as it is very lengthy and
	maintaining code becomes difficult.
   <h1 style="color:blue;text-align:center;">Header file</h1>

Code Example 2

Adding css file into html document

<link rel="stylesheet" type="text/css" href="yourstylesheetname.css">  /* add this line into head tag of the file with change in file name. */

I hope it will help you.

Code Example 3

<link rel="stylesheet" href="styles.css">

Code Example 4

<link rel="stylesheet" href="styles.css">

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