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<!doctype html> <html lang="en"> <head> <meta charset="utf-8"> <title>header demo</title> <script src="https://code.jquery.com/jquery-2.2.0.js"></script> </head> <body> <h1>Header 1</h1> <p>Contents 1</p> <h2>Header 2</h2> <p>Contents 2</p> <script> $(":header").css('background', 'red'); </script> </body> </html>
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