<!DOCTYPE html> <html> <head> <style> table { background: white } td { color: white } </style> <script> function runTest() { document.body.offsetHeight; document.getElementById("col").style.backgroundColor = "green"; } </script> </head> <body onload="runTest()"> <table> <col id="col" span="2"> <tr> <td>One</td> <td>Two</td> <td>Three</td> </tr> </table> </html>