We mentioned that BIRT uses CSS to define the styles for report items. BIRT also allows you to define the properties in a style sheet, then to apply the style to a report item, just as in HTML. The result is that you create the style once and use it multiple times. If you need to change the look of a report, you can change the style in one place rather then in many different report items. If you've defined your own styles when creating HTML pages, you're well on your way to understanding the BIRT style system. Styles can also be placed into BIRT libraries (Using Themes) and shared across reports.
Let's use the style feature to format the table header. Let's make the table header a blue bar with contrasting text. Instead of formatting each label one-by-one, we'll define a style, then apply it. To do this:
Notice that the new style has been applied to the label.
Next, let's apply the style to the other three header labels. (We could have done this in a single step by selecting all four when we defined the style. We're doing it in two steps just to show how it's done.)
The other three cells are now also formatted.
Suppose we wanted to change the style we just created. Here's how we find and change it.