remove problematic CSS in response to phil's concerns

- Will just use browser-specific grabby hands; other browsers too-bad
so-sad, I guess.
- Changed from attribute selectors to class ones, so that the dragging
override class selector has same specificity and therefore won't require
"!important"s on its "cursor" declarations.
Merge remote-tracking branch 'origin/58359238-make-reordering-discoverable' into testing