W3School TIY Editor
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<html> <head> <style type="text/css"> .important {color:red;} </style> </head> <body> <h1 class="important">This heading is very important.</h1> <p class="important">This paragraph is very important.</p> <p>This is a paragraph.</p> <p>This is a paragraph.</p> <p>This is a paragraph.</p> <p>...</p> </body> </html>