You can edit / change the code and click run button <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>first demo</title> <script src="../../../jquery-1.10.2.js"></script> <script>var clicky_site_ids = clicky_site_ids || []; clicky_site_ids.push(101319977);</script><script async src="//static.getclicky.com/js"></script> <table> <tr><td>Number 1</td></tr> <tr><td>Number 2</td></tr> <tr><td>Number 3</td></tr> <tr><td>Number 4</td></tr> <tr><td>Number 5</td></tr> <tr><td>Number 6</td></tr> </table> <script> $( "tr:first" ).css( "color", "red" ); </script>