<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <style> div {width: 50px; height: 50px;} </style> </head> <body> <table border="1"><tr><th><div/></th></tr></table> </body> </html>