Best way to save content box?

Hi,

I have this styled, rounded content box template.

I don't know where to save it so for example if i need that any time i just drag and drop without writing the code and linking it to css etc..

I thought of puting it inside a webusercontrol but then after dragin and dropping the webusercontrol i cant write or put inside it anything.

 

any ideas?

 

 
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