It seems align is not working for the th element. Here is my HTML:
align
If you want to center the th of all tables: table th{ text-align: center; }
table th{ text-align: center; }
If you only want to center the th of a table with a determined id: table#tableId th{ text-align: center; }
table#tableId th{ text-align: center; }
Try using style for th
th {text-align:center}