Cell Color

I am trying to set color of a cell using XML, but it won’t work. Please advise how to do that. I have tried couple of options.

#9999CC

Please, try to use the:

This did not worked, please advise. Thanks.

Unfortunately teh issue cannot be reproduced locally.
The provided code:
data
works well for me.

If the problem, still occurs for you please, provide with a complete demo/demo link, where the problem can be reconstructed locally.