This example has the following CSS include statement:
<link rel="stylesheet" href="css/switcher.php?default=blue.css" type="text/css" />
Because our default CSS file is blue.css this square will be blue the first time you load the example.
You can change the color of the square with these links:
Example 2 will show you how to switch multiple CSS files in a single HTML.
Please refer to our detailed and user-friendly documentation for details.