W3School TIY Editor
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<!DOCTYPE HTML> <html> <head> <style type="text/css"> h1 > strong {color:red;} </style> </head> <body> <h1>This is <strong>very</strong> <strong>very</strong> important.</h1> <h1>This is <em>really <strong>very</strong></em> important.</h1> </body> </html>