Complete the following steps:

1. Go to http://jqueryui.com/themeroller/.
2. Go to the Roll Your Own tab. Change the settings to create a custom theme; you can customize fonts, backgrounds, colors, and more. Or you can click the Gallery tab to select an existing theme.
3. Click the Download button and then click Download again on the Build Your Download page.
4. Save and unzip the theme .zip file to a folder within your Visual Studio project folder. In this example, we created a customtheme folder.
5. In the Solution Explorer, click Show All Files. Right-click customtheme and click Include In Project.
6. Click the C1Dialog smart tag to open the Tasks menu.
7. Enter the path to your custom theme .css in the Theme property, for example, \customtheme\css\custom-theme\jquery-ui-1.8.16.custom.css.

   

8. Run your project and note that the new theme is applied to C1Dialog.