W3School TIY Editor
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<!DOCTYPE html> <html> <head> <style>.highlight{background-color: yellow}</style> <script type="text/javascript" src="/jquery/jquery.js"></script> </head> <body> <p><span>Look:</span> <span>This is some text in a paragraph.</span> <span>This is a note about it.</span></p> <script>$("p span").first().addClass('highlight');</script> </body> </html>