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<!DOCTYPE html>
<html>
<head>
<style>
::-moz-selection { /* Code for Firefox */
   color: red;
   background: yellow;
}

::selection {
   color: red;
   background: yellow;
}
</style>
</head>
<body>

<h1>Select some text on this page:</h1>

<p>This is a paragraph.</p>
<div>This is some text in a div element.</div>

<p><strong>Note:</strong> ::selection is not supported in Internet Explorer 8 and earlier versions.</p>
<p><strong>Note:</strong> Firefox supports an alternative, the ::-moz-selection property.</p>

</body>
</html>