[users] Color will not show

[Christina]

Hi,
I am using your spreadsheet application and am really impressed with it, 
however I did something that I have no idea how to fix. I am using color to 
fill in cells, however whatever I did the color does not show any more. It 
still shows up on the browser that there is color there, but still no color.
Can you tell me how to fix this please?
Thank you,
Christina