Here the css has the code for the rounded corner.
You call the table class in the html whenever you want the round corner.
<!DOCTYPE html> <html> <head> <style type=text/css> .rounded_edges { -moz-border-radius: 15px; border-radius: 15px; border: 1px solid black; } </style> </head> <body> <table class="rounded_edges"> <tr> <th>Head 1</th> <th>Head 2</th> <th>Head 3</th> </tr> <tr> <td>Cell 1-1</td> <td>Cell 1-2</td> <td>Cell 1-3</td> </tr> <tr> <td>Cell 2-1</td> <td>Cell 2-2</td> <td>Cell 2-3</td> </tr> </table> </body> </html>
Source: