Tips for making Web Forms

In fact, the top three tables have three rows three columns, the secret of the hidden divider is rules, look at the source code of the three forms, we can see the <TABLE> tags have rules. It has three parameters (Cols,rows,none), and when rules=cols, the table hides the vertical divider so that we see only the rows of the table, and when rules=rows, the horizontal divider is hidden so that we can see only the columns of the table, and when the rules= When none, the portrait divider and the horizontal divider are all hidden.