To customize the report's appearance, styles can be used in a report. By default, ClientUI Report Designer provides some standard styles which can be used in a report. But it is still possible if you want to add a new style, or you want to completely override it. To learn about report styles, see Styles Overview.
To see the available report styles, you can browse it through the style gallery in ribbon.
To define new styles, ClientUI Reporting provides 2 approaches which can be used.
Internal styles are defined inside the report document. It means the styles are only owned by the report document it self. You can define it easily using the style editor which can be accessed from the ribbon. See the following illustration.
External styles are defined outside the report document. This mechanism allows styles to be shared among the report documents. Unlike internal style, you need to define it programmatically through code.