No worries @Adam_Thiel - that was a useful reminder that I did say I’d take a look at this! So, this is what I’ve been trying out so far:
And here are some screenshots of those settings in action:
Unfortunately there doesn’t seem to be any option using the standard CSS outline properties to do that.
Initially I was a bit unsure about including the ‘double’ and ‘offset’ options - but on seeing the effects you can create I think they could actually be a worthwhile addition. What do you all think?