div border-width: medium;
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en'> <head> <title>border-width</title> <style type='text/css'> div { padding: 3px; border-color: black; border-style: solid; background: mistyrose; margin: 5px; } div#thin { border-width: thin; } div#medium { border-width: medium; } div#thick { border-width: thick; } </style> </head> <body> <div id='thin'>thin</div> <div id='medium'>medium</div> <div id='thick'>thick</div> </body> </html>