The full dataview query is in the post above, localised to query files in my vault’s inbox.
The CSS isn’t part of the query; it is part of the styling used in the preview pane / output.
See the help directory for adding CSS snippets:
Angel
EDIT: the post below has a small sample CSS snippet and details about how to enable it. You could, perhaps, use it to see how CSS in Obsidian works. It is non-destructive and easily removed.