Hello abdu,
I am afraid I cannot completely understand the problem you are facing. If you need to change RadCalendar appearance you check the following links for more information.
RadCalendar styles
CSS Skin File Selectors
If the links mentioned above doesn't helped in your case I suggest you to create sample application and send it to is via formal support ticket. Thus we'll be able to debug it locally.
Regards,
Nikolay
the Telerik team
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