While adding tables to your site may be a visual cue for your users, making them look the way you want can be difficult. If you are wedded to including a table on a page, we strongly recommend building the table the way you want it in Microsoft Word and then copying it to your page.
Make sure that the Table Width and Height are set to 100%, this will allow the table to be responsive to different screen sizes.
Keep in mind the table properties may change the way the table appears on your page but not in the edited view. See comparison below.