Adjust the Remaining Gridview columns' width when other columns have hidden.

Having a gridview width of 800px, and 12 Boundfields' columns width as 30px. When hiding from 3rd columns to 12 columns, the remaining 1st and 2nd columns width will not be 30px but expand to 400px and 400px each. Task could be done remotely. Session could start at 10.00am kuala lumpur time