Hi Harald,
You can fetch the template for our control using VS Blend and modify the styles based on your requirement.
Steps to get template from Visual Studio Blend
1) Open the Visual Studio 2015 Blend
2) Drag and drop the control into the designer
3) Right click on the Syncfusion control and select Edit template
4) Now select “Edit a Copy” to get the template of the control.
5) Assign name to the template, this name could be used as style key for the control.
6) Now you can use the template of the control.
Please let us know, whether it is helpful.
Regards,
Keerthana J