Check out example codes for "how to use css". It will help you in understanding the concepts better.
Code Example 1
<link rel="stylesheet" href="file_name.css">
Code Example 2
<p style="color: blue; font-size: 46px;">
Code Example 3
<link rel="stylesheet" href="PathToYourFile.css">
Code Example 4
<style>
#panel{
height: 60%;
margin-top: 7%;
margin-left: 10%;
margin-right: 10%;
font-family: myriad-pro, sans-serif;
font-style: normal;
font-weight: 300;
}
</style>
Code Example 5
<link rel="stylesheet" type="text/css" href="mystyle.css">
Code Example 6
<link rel="stylesheet" href="stylesheet.css">
<div class="mydiv"></div>
<style>
.mydiv {
background-color: /*Color*/;
color: /*Another color*/;
}
</style>
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