Can we get an example of using a custom css and updating a variety of properties of the tree?

I have a custom css and using it to modify the node .. but is quite painful and I had to look at many 'issues' here to find how to do it.. as it has changed over time.

Would be nice to have a story that shows this:
1) customize node height and width, background etc
2) add and remove drag handle
3) Adjust padding between nodes and have the lines adjust accordingly
4) etc.

just some basic stuff.. but using css and not inline styles which seem to behave differently

In the image I attach can see I can't figure how to change the 'content' background of the node.. .just can't find the property.

I also want to shrink the padding between each child so they are closer together (compacted tree) and have the lines adjust accordingly.. just not easy to figure how to do that.

Can someone post a more complete example?