<!doctype html> <title>CSS Test Reference</title> <link rel="author" href="mailto:emilio@crisal.io" title="Emilio Cobos Álvarez"> <style> html, body { margin: 0; padding: 0; } .content { margin-top: 100px; width: 200px; height: 200px; background: blue; } </style> <body> <div class="content"></div> </body>