Create Css Class at runtime

Hi all,
I was wondering is it possible to create a css class at runtime?
I am unable to use the traditional method of doing so as one of the attributes need to be loaded at runtime.
As I am using the Coolite Toolkit, whenever i need to use a custom image onto one of the controls, the custom image path needs to be loaded in via a stylesheet class.

Please kindly assist.


Thank you.
Best Regards,
leroylll

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