Check out example codes for "css interne". It will help you in understanding the concepts better.

Code Example 1

<head>
 <style type="text/css">
 p {color:white; font-size: 10px;}
 .center {display: block; margin: 0 auto;}
 #button-go, #button-back {border: solid 1px black;}
 </style>
 </head>

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