<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> <title></title> <style type="text/css"> html, body{ height: 100%; margin: 0px; padding:0px; } table{ width: 100%; margin: 0px; padding: 0px; } table td{ margin: 0px; padding: 0px; } </style> </head> <body> <table> <tr> <td> <table> <tr><td style="height: 20px; border: 1px solid red">a</td></tr> <tr><td>b</td></tr> </table> </td> <td>c</td> </tr> </table> </body> </html>