Hide spent hours

[exstral]

First, thank you for this awesome extension!

We have a simple workflow and do not enter any "spent" hours. When enabling this extension there's a lot of very bright red zeros all over trello. Would it be possible to hide them if we never enter any 3/3 on any task and just use the estimation?

It would also be nice to change the red to something a bit darker and less eye-popping :)