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<html>
<head>
<title>CSS Styling</title>
<!-- `./` because the file is in the same directory as the HTML file -->
<link rel="stylesheet" type="text/css" href="./styles.css" />
</head>
<body>
<h1>CSS Styling</h1>
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="path/to/your/css/file.css">
</head>
<body>
<!-- Your HTML content goes here -->
</body>
</html>